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akbasic/src/parser.c

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Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
/**
* @file parser.c
* @brief Implements the recursive-descent parser.
*
* A faithful port of basicparser.go, with two changes. The reflection lookup for
* a verb's special parse path becomes a table lookup, and the debug.PrintStack()
* the reference calls on a parse failure is gone: an interpreter library does not
* dump the host's stack to stderr, and the akerr stack trace already carries what
* that call was for.
*/
#include <inttypes.h>
#include <string.h>
#include <akerror.h>
#include <akbasic/error.h>
#include <akbasic/parser.h>
#include <akbasic/verbs.h>
akerr_ErrorContext *akbasic_parser_init(akbasic_Parser *obj, akbasic_Runtime *runtime)
{
PREPARE_ERROR(errctx);
FAIL_ZERO_RETURN(errctx, (obj != NULL), AKERR_NULLPOINTER, "NULL parser in init");
FAIL_ZERO_RETURN(errctx, (runtime != NULL), AKERR_NULLPOINTER, "nil runtime argument");
obj->runtime = runtime;
Finish the language: every remaining verb group, and the defects that blocked them Closes groups A, C, D, E, F, H and J of TODO.md section 4, plus RESTORE and RENUMBER, and closes section 6 -- all seventeen reference defects. Seven of those turned out to have been fixed or never ported and nobody had written it down; the audit records the evidence for each. Two of the seventeen were real. math_plus mutated its left operand when the operand was mutable, so A# + 1 could modify A#; it was gated on FOR/NEXT coverage because NEXT relied on the mutation, so tests/for_next.c came first and NEXT now writes the counter back itself. And the binary operators summed both numeric fields of their right operand, which no BASIC program can reach -- that one needed a test written against the value API. Writing the tests turned up eight defects nobody had listed. Seven are fixed: IF A = 2 THEN was a parse error; only == worked IF ... AND ... was a parse error, because a condition parsed as one relation IF A = 1 OR B = 2 THEN was silently always false, and so was IF A THEN EXIT before any NEXT restarted the program and exhausted the variable pool READ never found a DATA line above it, and swallowed the lines between PRINT 2 + 2 at the prompt was filed as program text instead of answering a short read discarded its bytes, so COPY produced empty files every verb taking an argument list said "peek() returned nil token!" on none The eighth is not fixed and cannot be quietly: a FOR whose step overshoots runs its body one extra time, and FOR I = 1 TO 1 runs it zero times. The two errors cancel for a step of 1, which is why neither was noticed. Correcting them changes the expected output of a checked-in acceptance file, and tests/reference/README.md forbids editing one to suit this interpreter. It is tests/for_semantics.c in AKBASIC_KNOWN_FAILING_TESTS, asserting the correct contract, and TODO.md items 19 and 20. Sprites are real libakgl actors with a renderfunc of their own, because akgl_actor_render draws every sprite square and an actor has no per-axis scale. Both are filed upstream. SPRSAV takes an image file, an SSHAPE handle or a 63-element integer array -- a string here cannot hold a zero byte. Verbs that need hardware that does not exist are refused by name with the reason rather than faked: SYS, HEADER, COLLECT, BACKUP, BOOT, FILTER, and DIRECTORY, which is refused for a missing libakstdlib wrapper filed upstream. 94 tests in the default build, 93 with SDL, 94 under ASan and UBSan, doxygen clean. The Go acceptance corpus stayed green throughout. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-31 21:50:37 -04:00
obj->comparing = false;
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
SUCCEED_RETURN(errctx);
}
akerr_ErrorContext *akbasic_parser_zero(akbasic_Parser *obj)
{
PREPARE_ERROR(errctx);
FAIL_ZERO_RETURN(errctx, (obj != NULL), AKERR_NULLPOINTER, "nil self reference!");
PASS(errctx, akbasic_environment_zero_parser(obj->runtime->environment));
SUCCEED_RETURN(errctx);
}
akerr_ErrorContext *akbasic_parser_new_leaf(akbasic_Parser *obj, akbasic_ASTLeaf **dest)
{
PREPARE_ERROR(errctx);
PASS(errctx, akbasic_environment_new_leaf(obj->runtime->environment, dest));
SUCCEED_RETURN(errctx);
}
bool akbasic_parser_is_at_end(akbasic_Parser *obj)
{
akbasic_Environment *env = NULL;
if ( obj == NULL || obj->runtime == NULL || obj->runtime->environment == NULL ) {
return true;
}
env = obj->runtime->environment;
return (env->curtoken >= (AKBASIC_MAX_TOKENS - 1) || env->curtoken >= env->nexttoken);
}
akbasic_Token *akbasic_parser_peek(akbasic_Parser *obj)
{
if ( akbasic_parser_is_at_end(obj) ) {
return NULL;
}
return &obj->runtime->environment->tokens[obj->runtime->environment->curtoken];
}
akerr_ErrorContext *akbasic_parser_previous(akbasic_Parser *obj, akbasic_Token **dest)
{
PREPARE_ERROR(errctx);
FAIL_ZERO_RETURN(errctx, (obj != NULL && dest != NULL), AKERR_NULLPOINTER,
"NULL argument in previous");
FAIL_ZERO_RETURN(errctx, (obj->runtime->environment->curtoken != 0), AKBASIC_ERR_SYNTAX,
"Current token is index 0, no previous token");
*dest = &obj->runtime->environment->tokens[obj->runtime->environment->curtoken - 1];
SUCCEED_RETURN(errctx);
}
static bool check(akbasic_Parser *obj, akbasic_TokenType tokentype)
{
akbasic_Token *next = NULL;
if ( akbasic_parser_is_at_end(obj) ) {
return false;
}
next = akbasic_parser_peek(obj);
return (next != NULL && next->tokentype == tokentype);
}
static void advance(akbasic_Parser *obj)
{
if ( !akbasic_parser_is_at_end(obj) ) {
obj->runtime->environment->curtoken += 1;
}
}
bool akbasic_parser_match(akbasic_Parser *obj, const akbasic_TokenType *types, int count)
{
int i = 0;
for ( i = 0; i < count; i++ ) {
if ( check(obj, types[i]) ) {
advance(obj);
return true;
}
}
return false;
}
bool akbasic_parser_match1(akbasic_Parser *obj, akbasic_TokenType type)
{
return akbasic_parser_match(obj, &type, 1);
}
akerr_ErrorContext *akbasic_parser_error(akbasic_Parser *obj, const char *message)
{
PREPARE_ERROR(errctx);
akbasic_Token *token = NULL;
token = akbasic_parser_peek(obj);
obj->runtime->environment->errorToken = token;
FAIL_ZERO_RETURN(errctx, (token != NULL), AKBASIC_ERR_SYNTAX, "peek() returned nil token!");
if ( token->tokentype == AKBASIC_TOK_EOF ) {
FAIL_RETURN(errctx, AKBASIC_ERR_SYNTAX, "%" PRId64 " at end %s", token->lineno, message);
}
FAIL_RETURN(errctx, AKBASIC_ERR_SYNTAX, "%" PRId64 " at '%s', %s",
token->lineno, token->lexeme, message);
}
static akerr_ErrorContext *consume(akbasic_Parser *obj, akbasic_TokenType tokentype, const char *message)
{
PREPARE_ERROR(errctx);
if ( check(obj, tokentype) ) {
advance(obj);
SUCCEED_RETURN(errctx);
}
PASS(errctx, akbasic_parser_error(obj, message));
SUCCEED_RETURN(errctx);
}
/* Forward declarations for the grammar chain. */
static akerr_ErrorContext *logicalandor(akbasic_Parser *obj, akbasic_ASTLeaf **dest);
static akerr_ErrorContext *logicalnot(akbasic_Parser *obj, akbasic_ASTLeaf **dest);
static akerr_ErrorContext *subtraction(akbasic_Parser *obj, akbasic_ASTLeaf **dest);
static akerr_ErrorContext *addition(akbasic_Parser *obj, akbasic_ASTLeaf **dest);
static akerr_ErrorContext *multiplication(akbasic_Parser *obj, akbasic_ASTLeaf **dest);
static akerr_ErrorContext *division(akbasic_Parser *obj, akbasic_ASTLeaf **dest);
static akerr_ErrorContext *unary(akbasic_Parser *obj, akbasic_ASTLeaf **dest);
static akerr_ErrorContext *exponent(akbasic_Parser *obj, akbasic_ASTLeaf **dest);
static akerr_ErrorContext *function_call(akbasic_Parser *obj, akbasic_ASTLeaf **dest);
bool akbasic_parser_skip_separators(akbasic_Parser *obj)
{
while ( akbasic_parser_match1(obj, AKBASIC_TOK_COLON) ) {
/*
* A run of them, so `10 PRINT 1 :: PRINT 2` and a trailing colon both
* work. An empty statement is not an error on a C128 and is not one
* here.
*/
}
return !akbasic_parser_is_at_end(obj);
}
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
akerr_ErrorContext *akbasic_parser_parse(akbasic_Parser *obj, akbasic_ASTLeaf **dest)
{
PREPARE_ERROR(errctx);
FAIL_ZERO_RETURN(errctx, (obj != NULL && dest != NULL), AKERR_NULLPOINTER,
"NULL argument in parse");
*dest = NULL;
/*
* Statements are separated by colons. The scanner has emitted the token
* since the port began and nothing consumed it, so a line with two
* statements on it was a parse error -- TODO.md section 4.
*
* Nothing after the separators is a line that ended in one. That is not an
* error, so the caller gets a NULL leaf and skips it.
*/
if ( !akbasic_parser_skip_separators(obj) ) {
SUCCEED_RETURN(errctx);
}
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
PASS(errctx, akbasic_parser_command(obj, dest));
SUCCEED_RETURN(errctx);
}
akerr_ErrorContext *akbasic_parser_command(akbasic_Parser *obj, akbasic_ASTLeaf **dest)
{
PREPARE_ERROR(errctx);
static const akbasic_TokenType COMMANDS[] = {
AKBASIC_TOK_COMMAND, AKBASIC_TOK_COMMAND_IMMEDIATE
};
akbasic_ASTLeaf *expr = NULL;
akbasic_ASTLeaf *right = NULL;
akbasic_Token *operator_ = NULL;
akbasic_Token *righttoken = NULL;
const akbasic_Verb *verb = NULL;
akbasic_TokenType optype = AKBASIC_TOK_UNDEFINED;
char opname[AKBASIC_MAX_LINE_LENGTH];
if ( !akbasic_parser_match(obj, COMMANDS, 2) ) {
PASS(errctx, akbasic_parser_assignment(obj, dest));
SUCCEED_RETURN(errctx);
}
PASS(errctx, akbasic_parser_previous(obj, &operator_));
optype = operator_->tokentype;
strncpy(opname, operator_->lexeme, sizeof(opname) - 1);
opname[sizeof(opname) - 1] = '\0';
/* Does this verb need its own parse path? */
PASS(errctx, akbasic_verb_lookup(opname, &verb));
if ( verb != NULL && verb->parse != NULL ) {
PASS(errctx, verb->parse(obj, dest));
SUCCEED_RETURN(errctx);
}
/*
* Some verbs take no rval. Do not fail when there is not one -- but do fail
* when there is one and it will not parse.
*/
righttoken = akbasic_parser_peek(obj);
if ( righttoken != NULL && righttoken->tokentype != AKBASIC_TOK_UNDEFINED &&
righttoken->tokentype != AKBASIC_TOK_COLON ) {
/*
* A colon ends the statement, so `PRINT : PRINT "X"` is a bare PRINT
* followed by another statement rather than a PRINT of whatever a colon
* evaluates to.
*/
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
PASS(errctx, akbasic_parser_expression(obj, &right));
}
PASS(errctx, akbasic_parser_new_leaf(obj, &expr));
if ( optype == AKBASIC_TOK_COMMAND_IMMEDIATE ) {
PASS(errctx, akbasic_leaf_new_immediate_command(expr, opname, right));
} else {
PASS(errctx, akbasic_leaf_new_command(expr, opname, right));
}
*dest = expr;
SUCCEED_RETURN(errctx);
}
akerr_ErrorContext *akbasic_parser_assignment(akbasic_Parser *obj, akbasic_ASTLeaf **dest)
{
PREPARE_ERROR(errctx);
akbasic_ASTLeaf *identifier = NULL;
akbasic_ASTLeaf *expr = NULL;
akbasic_ASTLeaf *right = NULL;
PASS(errctx, akbasic_parser_expression(obj, &identifier));
Add records: TYPE, DIM ... AS, field access, copy on assign BASIC 7.0 has no records at all, so none of this is a port. The `@` suffix was not invented either: the Go reference reserved IDENTIFIER_STRUCT and never used it, and src/grammar.c rendered such a leaf as "NOT IMPLEMENTED" until now. Declaring the type is what buys the storage model. A TYPE states its fields, so an instance has a known slot count and is laid out exactly as an array is -- one contiguous run from the same value pool DIM already draws from, with field access as offset arithmetic. No new pool holds data; the only new table holds descriptors. A nested value flattens into its container's run, which is why LINE with two POINTs and a string is five slots rather than three. Each field takes its type from its own suffix, the same rule every other name here follows, so a field list needs no type column. An `@` field is the exception and has to name its type, because three primitive types fit in three suffix characters and N declared types do not fit in one. The declaration is prescanned before the program runs, like labels and DATA and for the same reason: it has to be in effect wherever control goes. Three passes, each for a case the one before cannot do -- names first so a field can refer to a type declared later, then field lists, then sizes by repeated resolution. What never resolves is a cycle of by-value containment, so "a TYPE cannot contain itself by value" is a diagnosis rather than an assumption, and the message says to use PTR TO instead. Assignment copies. That interception is the whole feature and it cannot live in akbasic_value_clone(), which copies one slot -- and one slot holds a *reference* to an instance rather than the instance, so going through it would alias. A structure is intercepted before that path and its slots are copied one at a time, walking the descriptor rather than memcpy-ing the run, because a pointer field must copy its reference where a value field must copy its slots. Two smaller things the work required. All three prescans now sit inside one ATTEMPT: a malformed declaration is the program's mistake, and it was printing a stack trace and taking the driver with it, which is the boundary goal 3 exists to draw. And a fresh variable's structtype is -1 rather than the 0 a memset leaves, because 0 is a valid type index and every new variable was claiming to be the first type declared. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-08-01 11:39:47 -04:00
/*
* A field access is assignable too, and it is not an identifier: the
* name on the left of the = is reached by walking a chain rather than by
* looking one name up. Both spellings continue into the = below.
*/
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
if ( identifier == NULL ||
(identifier->leaftype != AKBASIC_LEAF_IDENTIFIER_INT &&
identifier->leaftype != AKBASIC_LEAF_IDENTIFIER_FLOAT &&
Add records: TYPE, DIM ... AS, field access, copy on assign BASIC 7.0 has no records at all, so none of this is a port. The `@` suffix was not invented either: the Go reference reserved IDENTIFIER_STRUCT and never used it, and src/grammar.c rendered such a leaf as "NOT IMPLEMENTED" until now. Declaring the type is what buys the storage model. A TYPE states its fields, so an instance has a known slot count and is laid out exactly as an array is -- one contiguous run from the same value pool DIM already draws from, with field access as offset arithmetic. No new pool holds data; the only new table holds descriptors. A nested value flattens into its container's run, which is why LINE with two POINTs and a string is five slots rather than three. Each field takes its type from its own suffix, the same rule every other name here follows, so a field list needs no type column. An `@` field is the exception and has to name its type, because three primitive types fit in three suffix characters and N declared types do not fit in one. The declaration is prescanned before the program runs, like labels and DATA and for the same reason: it has to be in effect wherever control goes. Three passes, each for a case the one before cannot do -- names first so a field can refer to a type declared later, then field lists, then sizes by repeated resolution. What never resolves is a cycle of by-value containment, so "a TYPE cannot contain itself by value" is a diagnosis rather than an assumption, and the message says to use PTR TO instead. Assignment copies. That interception is the whole feature and it cannot live in akbasic_value_clone(), which copies one slot -- and one slot holds a *reference* to an instance rather than the instance, so going through it would alias. A structure is intercepted before that path and its slots are copied one at a time, walking the descriptor rather than memcpy-ing the run, because a pointer field must copy its reference where a value field must copy its slots. Two smaller things the work required. All three prescans now sit inside one ATTEMPT: a malformed declaration is the program's mistake, and it was printing a stack trace and taking the driver with it, which is the boundary goal 3 exists to draw. And a fresh variable's structtype is -1 rather than the 0 a memset leaves, because 0 is a valid type index and every new variable was claiming to be the first type declared. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-08-01 11:39:47 -04:00
identifier->leaftype != AKBASIC_LEAF_IDENTIFIER_STRING &&
identifier->leaftype != AKBASIC_LEAF_IDENTIFIER_STRUCT &&
identifier->leaftype != AKBASIC_LEAF_FIELD) ) {
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
*dest = identifier;
SUCCEED_RETURN(errctx);
}
if ( akbasic_parser_match1(obj, AKBASIC_TOK_ASSIGNMENT) ) {
PASS(errctx, akbasic_parser_expression(obj, &right));
PASS(errctx, akbasic_parser_new_leaf(obj, &expr));
PASS(errctx, akbasic_leaf_new_binary(expr, identifier, AKBASIC_TOK_ASSIGNMENT, right));
*dest = expr;
SUCCEED_RETURN(errctx);
}
*dest = identifier;
SUCCEED_RETURN(errctx);
}
/*
* An argument list is just .right-joined expressions continuing ad infinitum.
* When requireparens is false and there is no opening paren, this still builds a
* list -- that is how DATA and READ take a bare comma-separated series.
*/
akerr_ErrorContext *akbasic_parser_argument_list(akbasic_Parser *obj, akbasic_TokenType arglisttype, bool requireparens, akbasic_ASTLeaf **dest)
{
PREPARE_ERROR(errctx);
akbasic_ASTLeaf *arglist = NULL;
akbasic_ASTLeaf *expr = NULL;
*dest = NULL;
if ( !akbasic_parser_match1(obj, AKBASIC_TOK_LEFT_PAREN) && requireparens ) {
SUCCEED_RETURN(errctx);
}
FAIL_ZERO_RETURN(errctx,
(arglisttype == AKBASIC_TOK_ARRAY_SUBSCRIPT ||
arglisttype == AKBASIC_TOK_FUNCTION_ARGUMENT),
AKBASIC_ERR_SYNTAX,
"argumentList expects argListType [ARRAY_SUBSCRIPT || FUNCTION_ARGUMENT]");
PASS(errctx, akbasic_parser_new_leaf(obj, &arglist));
arglist->leaftype = AKBASIC_LEAF_ARGUMENTLIST;
arglist->operator_ = arglisttype;
PASS(errctx, akbasic_parser_expression(obj, &arglist->right));
/*
* Siblings chain through .next, never through .right. Every leaf type that
* can be an argument already uses .right for something of its own -- a
* unary's operand, a binary's right-hand side -- and reusing it here is what
* made ABS(-9) count as two arguments. See akbasic_ASTLeaf.next.
*/
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
expr = arglist->right;
while ( expr != NULL && akbasic_parser_match1(obj, AKBASIC_TOK_COMMA) ) {
PASS(errctx, akbasic_parser_expression(obj, &expr->next));
expr = expr->next;
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
}
if ( !akbasic_parser_match1(obj, AKBASIC_TOK_RIGHT_PAREN) && requireparens ) {
FAIL_RETURN(errctx, AKBASIC_ERR_SYNTAX, "Unbalanced parenthesis");
}
*dest = arglist;
SUCCEED_RETURN(errctx);
}
akerr_ErrorContext *akbasic_parser_expression(akbasic_Parser *obj, akbasic_ASTLeaf **dest)
{
PREPARE_ERROR(errctx);
PASS(errctx, logicalandor(obj, dest));
SUCCEED_RETURN(errctx);
}
static akerr_ErrorContext *logicalandor(akbasic_Parser *obj, akbasic_ASTLeaf **dest)
{
PREPARE_ERROR(errctx);
static const akbasic_TokenType OPS[] = { AKBASIC_TOK_AND, AKBASIC_TOK_OR };
akbasic_ASTLeaf *left = NULL;
akbasic_ASTLeaf *right = NULL;
akbasic_ASTLeaf *expr = NULL;
akbasic_Token *operator_ = NULL;
PASS(errctx, logicalnot(obj, &left));
if ( akbasic_parser_match(obj, OPS, 2) ) {
PASS(errctx, akbasic_parser_previous(obj, &operator_));
PASS(errctx, logicalnot(obj, &right));
PASS(errctx, akbasic_parser_new_leaf(obj, &expr));
PASS(errctx, akbasic_leaf_new_binary(expr, left, operator_->tokentype, right));
*dest = expr;
SUCCEED_RETURN(errctx);
}
*dest = left;
SUCCEED_RETURN(errctx);
}
static akerr_ErrorContext *logicalnot(akbasic_Parser *obj, akbasic_ASTLeaf **dest)
{
PREPARE_ERROR(errctx);
akbasic_ASTLeaf *right = NULL;
akbasic_ASTLeaf *expr = NULL;
akbasic_Token *operator_ = NULL;
if ( akbasic_parser_match1(obj, AKBASIC_TOK_NOT) ) {
PASS(errctx, akbasic_parser_previous(obj, &operator_));
PASS(errctx, akbasic_parser_relation(obj, &right));
PASS(errctx, akbasic_parser_new_leaf(obj, &expr));
PASS(errctx, akbasic_leaf_new_unary(expr, operator_->tokentype, right));
*dest = expr;
SUCCEED_RETURN(errctx);
}
PASS(errctx, akbasic_parser_relation(obj, dest));
SUCCEED_RETURN(errctx);
}
akerr_ErrorContext *akbasic_parser_relation(akbasic_Parser *obj, akbasic_ASTLeaf **dest)
{
PREPARE_ERROR(errctx);
Finish the language: every remaining verb group, and the defects that blocked them Closes groups A, C, D, E, F, H and J of TODO.md section 4, plus RESTORE and RENUMBER, and closes section 6 -- all seventeen reference defects. Seven of those turned out to have been fixed or never ported and nobody had written it down; the audit records the evidence for each. Two of the seventeen were real. math_plus mutated its left operand when the operand was mutable, so A# + 1 could modify A#; it was gated on FOR/NEXT coverage because NEXT relied on the mutation, so tests/for_next.c came first and NEXT now writes the counter back itself. And the binary operators summed both numeric fields of their right operand, which no BASIC program can reach -- that one needed a test written against the value API. Writing the tests turned up eight defects nobody had listed. Seven are fixed: IF A = 2 THEN was a parse error; only == worked IF ... AND ... was a parse error, because a condition parsed as one relation IF A = 1 OR B = 2 THEN was silently always false, and so was IF A THEN EXIT before any NEXT restarted the program and exhausted the variable pool READ never found a DATA line above it, and swallowed the lines between PRINT 2 + 2 at the prompt was filed as program text instead of answering a short read discarded its bytes, so COPY produced empty files every verb taking an argument list said "peek() returned nil token!" on none The eighth is not fixed and cannot be quietly: a FOR whose step overshoots runs its body one extra time, and FOR I = 1 TO 1 runs it zero times. The two errors cancel for a step of 1, which is why neither was noticed. Correcting them changes the expected output of a checked-in acceptance file, and tests/reference/README.md forbids editing one to suit this interpreter. It is tests/for_semantics.c in AKBASIC_KNOWN_FAILING_TESTS, asserting the correct contract, and TODO.md items 19 and 20. Sprites are real libakgl actors with a renderfunc of their own, because akgl_actor_render draws every sprite square and an actor has no per-axis scale. Both are filed upstream. SPRSAV takes an image file, an SSHAPE handle or a 63-element integer array -- a string here cannot hold a zero byte. Verbs that need hardware that does not exist are refused by name with the reason rather than faked: SYS, HEADER, COLLECT, BACKUP, BOOT, FILTER, and DIRECTORY, which is refused for a missing libakstdlib wrapper filed upstream. 94 tests in the default build, 93 with SDL, 94 under ASan and UBSan, doxygen clean. The Go acceptance corpus stayed green throughout. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-31 21:50:37 -04:00
/*
* A lone `=` is an equality test here when the caller has said a condition
* is what it is parsing. `==` keeps working either way, which is what the Go
* reference used and what the whole checked-in corpus is written in. See
* akbasic_Parser::comparing and TODO.md section 5.
*/
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
static const akbasic_TokenType OPS[] = {
AKBASIC_TOK_LESS_THAN, AKBASIC_TOK_LESS_THAN_EQUAL, AKBASIC_TOK_EQUAL,
Finish the language: every remaining verb group, and the defects that blocked them Closes groups A, C, D, E, F, H and J of TODO.md section 4, plus RESTORE and RENUMBER, and closes section 6 -- all seventeen reference defects. Seven of those turned out to have been fixed or never ported and nobody had written it down; the audit records the evidence for each. Two of the seventeen were real. math_plus mutated its left operand when the operand was mutable, so A# + 1 could modify A#; it was gated on FOR/NEXT coverage because NEXT relied on the mutation, so tests/for_next.c came first and NEXT now writes the counter back itself. And the binary operators summed both numeric fields of their right operand, which no BASIC program can reach -- that one needed a test written against the value API. Writing the tests turned up eight defects nobody had listed. Seven are fixed: IF A = 2 THEN was a parse error; only == worked IF ... AND ... was a parse error, because a condition parsed as one relation IF A = 1 OR B = 2 THEN was silently always false, and so was IF A THEN EXIT before any NEXT restarted the program and exhausted the variable pool READ never found a DATA line above it, and swallowed the lines between PRINT 2 + 2 at the prompt was filed as program text instead of answering a short read discarded its bytes, so COPY produced empty files every verb taking an argument list said "peek() returned nil token!" on none The eighth is not fixed and cannot be quietly: a FOR whose step overshoots runs its body one extra time, and FOR I = 1 TO 1 runs it zero times. The two errors cancel for a step of 1, which is why neither was noticed. Correcting them changes the expected output of a checked-in acceptance file, and tests/reference/README.md forbids editing one to suit this interpreter. It is tests/for_semantics.c in AKBASIC_KNOWN_FAILING_TESTS, asserting the correct contract, and TODO.md items 19 and 20. Sprites are real libakgl actors with a renderfunc of their own, because akgl_actor_render draws every sprite square and an actor has no per-axis scale. Both are filed upstream. SPRSAV takes an image file, an SSHAPE handle or a 63-element integer array -- a string here cannot hold a zero byte. Verbs that need hardware that does not exist are refused by name with the reason rather than faked: SYS, HEADER, COLLECT, BACKUP, BOOT, FILTER, and DIRECTORY, which is refused for a missing libakstdlib wrapper filed upstream. 94 tests in the default build, 93 with SDL, 94 under ASan and UBSan, doxygen clean. The Go acceptance corpus stayed green throughout. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-31 21:50:37 -04:00
AKBASIC_TOK_NOT_EQUAL, AKBASIC_TOK_GREATER_THAN, AKBASIC_TOK_GREATER_THAN_EQUAL,
AKBASIC_TOK_ASSIGNMENT
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
};
akbasic_ASTLeaf *left = NULL;
akbasic_ASTLeaf *right = NULL;
akbasic_ASTLeaf *expr = NULL;
akbasic_Token *operator_ = NULL;
Finish the language: every remaining verb group, and the defects that blocked them Closes groups A, C, D, E, F, H and J of TODO.md section 4, plus RESTORE and RENUMBER, and closes section 6 -- all seventeen reference defects. Seven of those turned out to have been fixed or never ported and nobody had written it down; the audit records the evidence for each. Two of the seventeen were real. math_plus mutated its left operand when the operand was mutable, so A# + 1 could modify A#; it was gated on FOR/NEXT coverage because NEXT relied on the mutation, so tests/for_next.c came first and NEXT now writes the counter back itself. And the binary operators summed both numeric fields of their right operand, which no BASIC program can reach -- that one needed a test written against the value API. Writing the tests turned up eight defects nobody had listed. Seven are fixed: IF A = 2 THEN was a parse error; only == worked IF ... AND ... was a parse error, because a condition parsed as one relation IF A = 1 OR B = 2 THEN was silently always false, and so was IF A THEN EXIT before any NEXT restarted the program and exhausted the variable pool READ never found a DATA line above it, and swallowed the lines between PRINT 2 + 2 at the prompt was filed as program text instead of answering a short read discarded its bytes, so COPY produced empty files every verb taking an argument list said "peek() returned nil token!" on none The eighth is not fixed and cannot be quietly: a FOR whose step overshoots runs its body one extra time, and FOR I = 1 TO 1 runs it zero times. The two errors cancel for a step of 1, which is why neither was noticed. Correcting them changes the expected output of a checked-in acceptance file, and tests/reference/README.md forbids editing one to suit this interpreter. It is tests/for_semantics.c in AKBASIC_KNOWN_FAILING_TESTS, asserting the correct contract, and TODO.md items 19 and 20. Sprites are real libakgl actors with a renderfunc of their own, because akgl_actor_render draws every sprite square and an actor has no per-axis scale. Both are filed upstream. SPRSAV takes an image file, an SSHAPE handle or a 63-element integer array -- a string here cannot hold a zero byte. Verbs that need hardware that does not exist are refused by name with the reason rather than faked: SYS, HEADER, COLLECT, BACKUP, BOOT, FILTER, and DIRECTORY, which is refused for a missing libakstdlib wrapper filed upstream. 94 tests in the default build, 93 with SDL, 94 under ASan and UBSan, doxygen clean. The Go acceptance corpus stayed green throughout. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-31 21:50:37 -04:00
akbasic_TokenType op = AKBASIC_TOK_UNDEFINED;
/*
* ASSIGNMENT is the last entry, and it is only offered while `comparing` --
* see akbasic_Parser. Outside a condition `=` has to stay an assignment, or
* `A# = 2` stops storing anything and `FOR I# = 1 TO 5` never initializes
* its counter.
*/
int opcount = (obj->comparing ? 7 : 6);
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
PASS(errctx, subtraction(obj, &left));
Finish the language: every remaining verb group, and the defects that blocked them Closes groups A, C, D, E, F, H and J of TODO.md section 4, plus RESTORE and RENUMBER, and closes section 6 -- all seventeen reference defects. Seven of those turned out to have been fixed or never ported and nobody had written it down; the audit records the evidence for each. Two of the seventeen were real. math_plus mutated its left operand when the operand was mutable, so A# + 1 could modify A#; it was gated on FOR/NEXT coverage because NEXT relied on the mutation, so tests/for_next.c came first and NEXT now writes the counter back itself. And the binary operators summed both numeric fields of their right operand, which no BASIC program can reach -- that one needed a test written against the value API. Writing the tests turned up eight defects nobody had listed. Seven are fixed: IF A = 2 THEN was a parse error; only == worked IF ... AND ... was a parse error, because a condition parsed as one relation IF A = 1 OR B = 2 THEN was silently always false, and so was IF A THEN EXIT before any NEXT restarted the program and exhausted the variable pool READ never found a DATA line above it, and swallowed the lines between PRINT 2 + 2 at the prompt was filed as program text instead of answering a short read discarded its bytes, so COPY produced empty files every verb taking an argument list said "peek() returned nil token!" on none The eighth is not fixed and cannot be quietly: a FOR whose step overshoots runs its body one extra time, and FOR I = 1 TO 1 runs it zero times. The two errors cancel for a step of 1, which is why neither was noticed. Correcting them changes the expected output of a checked-in acceptance file, and tests/reference/README.md forbids editing one to suit this interpreter. It is tests/for_semantics.c in AKBASIC_KNOWN_FAILING_TESTS, asserting the correct contract, and TODO.md items 19 and 20. Sprites are real libakgl actors with a renderfunc of their own, because akgl_actor_render draws every sprite square and an actor has no per-axis scale. Both are filed upstream. SPRSAV takes an image file, an SSHAPE handle or a 63-element integer array -- a string here cannot hold a zero byte. Verbs that need hardware that does not exist are refused by name with the reason rather than faked: SYS, HEADER, COLLECT, BACKUP, BOOT, FILTER, and DIRECTORY, which is refused for a missing libakstdlib wrapper filed upstream. 94 tests in the default build, 93 with SDL, 94 under ASan and UBSan, doxygen clean. The Go acceptance corpus stayed green throughout. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-31 21:50:37 -04:00
if ( akbasic_parser_match(obj, OPS, opcount) ) {
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
PASS(errctx, akbasic_parser_previous(obj, &operator_));
Finish the language: every remaining verb group, and the defects that blocked them Closes groups A, C, D, E, F, H and J of TODO.md section 4, plus RESTORE and RENUMBER, and closes section 6 -- all seventeen reference defects. Seven of those turned out to have been fixed or never ported and nobody had written it down; the audit records the evidence for each. Two of the seventeen were real. math_plus mutated its left operand when the operand was mutable, so A# + 1 could modify A#; it was gated on FOR/NEXT coverage because NEXT relied on the mutation, so tests/for_next.c came first and NEXT now writes the counter back itself. And the binary operators summed both numeric fields of their right operand, which no BASIC program can reach -- that one needed a test written against the value API. Writing the tests turned up eight defects nobody had listed. Seven are fixed: IF A = 2 THEN was a parse error; only == worked IF ... AND ... was a parse error, because a condition parsed as one relation IF A = 1 OR B = 2 THEN was silently always false, and so was IF A THEN EXIT before any NEXT restarted the program and exhausted the variable pool READ never found a DATA line above it, and swallowed the lines between PRINT 2 + 2 at the prompt was filed as program text instead of answering a short read discarded its bytes, so COPY produced empty files every verb taking an argument list said "peek() returned nil token!" on none The eighth is not fixed and cannot be quietly: a FOR whose step overshoots runs its body one extra time, and FOR I = 1 TO 1 runs it zero times. The two errors cancel for a step of 1, which is why neither was noticed. Correcting them changes the expected output of a checked-in acceptance file, and tests/reference/README.md forbids editing one to suit this interpreter. It is tests/for_semantics.c in AKBASIC_KNOWN_FAILING_TESTS, asserting the correct contract, and TODO.md items 19 and 20. Sprites are real libakgl actors with a renderfunc of their own, because akgl_actor_render draws every sprite square and an actor has no per-axis scale. Both are filed upstream. SPRSAV takes an image file, an SSHAPE handle or a 63-element integer array -- a string here cannot hold a zero byte. Verbs that need hardware that does not exist are refused by name with the reason rather than faked: SYS, HEADER, COLLECT, BACKUP, BOOT, FILTER, and DIRECTORY, which is refused for a missing libakstdlib wrapper filed upstream. 94 tests in the default build, 93 with SDL, 94 under ASan and UBSan, doxygen clean. The Go acceptance corpus stayed green throughout. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-31 21:50:37 -04:00
op = operator_->tokentype;
if ( op == AKBASIC_TOK_ASSIGNMENT ) {
op = AKBASIC_TOK_EQUAL;
}
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
PASS(errctx, subtraction(obj, &right));
PASS(errctx, akbasic_parser_new_leaf(obj, &expr));
Finish the language: every remaining verb group, and the defects that blocked them Closes groups A, C, D, E, F, H and J of TODO.md section 4, plus RESTORE and RENUMBER, and closes section 6 -- all seventeen reference defects. Seven of those turned out to have been fixed or never ported and nobody had written it down; the audit records the evidence for each. Two of the seventeen were real. math_plus mutated its left operand when the operand was mutable, so A# + 1 could modify A#; it was gated on FOR/NEXT coverage because NEXT relied on the mutation, so tests/for_next.c came first and NEXT now writes the counter back itself. And the binary operators summed both numeric fields of their right operand, which no BASIC program can reach -- that one needed a test written against the value API. Writing the tests turned up eight defects nobody had listed. Seven are fixed: IF A = 2 THEN was a parse error; only == worked IF ... AND ... was a parse error, because a condition parsed as one relation IF A = 1 OR B = 2 THEN was silently always false, and so was IF A THEN EXIT before any NEXT restarted the program and exhausted the variable pool READ never found a DATA line above it, and swallowed the lines between PRINT 2 + 2 at the prompt was filed as program text instead of answering a short read discarded its bytes, so COPY produced empty files every verb taking an argument list said "peek() returned nil token!" on none The eighth is not fixed and cannot be quietly: a FOR whose step overshoots runs its body one extra time, and FOR I = 1 TO 1 runs it zero times. The two errors cancel for a step of 1, which is why neither was noticed. Correcting them changes the expected output of a checked-in acceptance file, and tests/reference/README.md forbids editing one to suit this interpreter. It is tests/for_semantics.c in AKBASIC_KNOWN_FAILING_TESTS, asserting the correct contract, and TODO.md items 19 and 20. Sprites are real libakgl actors with a renderfunc of their own, because akgl_actor_render draws every sprite square and an actor has no per-axis scale. Both are filed upstream. SPRSAV takes an image file, an SSHAPE handle or a 63-element integer array -- a string here cannot hold a zero byte. Verbs that need hardware that does not exist are refused by name with the reason rather than faked: SYS, HEADER, COLLECT, BACKUP, BOOT, FILTER, and DIRECTORY, which is refused for a missing libakstdlib wrapper filed upstream. 94 tests in the default build, 93 with SDL, 94 under ASan and UBSan, doxygen clean. The Go acceptance corpus stayed green throughout. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-31 21:50:37 -04:00
PASS(errctx, akbasic_leaf_new_binary(expr, left, op, right));
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
*dest = expr;
SUCCEED_RETURN(errctx);
}
*dest = left;
SUCCEED_RETURN(errctx);
}
/*
* Loops, where the reference returns after one operator (basicparser.go:329).
* That asymmetry was reproduced faithfully at first and is TODO.md section 6
* item 12: `1 - 2 - 3` computed `1 - 2` and abandoned the rest of the line,
* which the statement loop then picked up as a second statement and discarded.
* A wrong answer, silently -- the highest-impact item on that list.
*
* Left-associative, matching addition, multiplication and division here and
* matching a C128, which evaluates a run of same-precedence operators left to
* right.
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
*/
static akerr_ErrorContext *subtraction(akbasic_Parser *obj, akbasic_ASTLeaf **dest)
{
PREPARE_ERROR(errctx);
akbasic_ASTLeaf *left = NULL;
akbasic_ASTLeaf *right = NULL;
akbasic_ASTLeaf *expr = NULL;
akbasic_Token *operator_ = NULL;
PASS(errctx, addition(obj, &left));
while ( akbasic_parser_match1(obj, AKBASIC_TOK_MINUS) ) {
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
PASS(errctx, akbasic_parser_previous(obj, &operator_));
PASS(errctx, addition(obj, &right));
if ( expr != NULL ) {
left = expr;
}
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
PASS(errctx, akbasic_parser_new_leaf(obj, &expr));
PASS(errctx, akbasic_leaf_new_binary(expr, left, operator_->tokentype, right));
}
*dest = (expr != NULL ? expr : left);
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
SUCCEED_RETURN(errctx);
}
static akerr_ErrorContext *addition(akbasic_Parser *obj, akbasic_ASTLeaf **dest)
{
PREPARE_ERROR(errctx);
akbasic_ASTLeaf *left = NULL;
akbasic_ASTLeaf *right = NULL;
akbasic_ASTLeaf *expr = NULL;
akbasic_Token *operator_ = NULL;
PASS(errctx, multiplication(obj, &left));
while ( akbasic_parser_match1(obj, AKBASIC_TOK_PLUS) ) {
PASS(errctx, akbasic_parser_previous(obj, &operator_));
PASS(errctx, multiplication(obj, &right));
if ( expr != NULL ) {
left = expr;
}
PASS(errctx, akbasic_parser_new_leaf(obj, &expr));
PASS(errctx, akbasic_leaf_new_binary(expr, left, operator_->tokentype, right));
}
*dest = (expr != NULL ? expr : left);
SUCCEED_RETURN(errctx);
}
static akerr_ErrorContext *multiplication(akbasic_Parser *obj, akbasic_ASTLeaf **dest)
{
PREPARE_ERROR(errctx);
akbasic_ASTLeaf *left = NULL;
akbasic_ASTLeaf *right = NULL;
akbasic_ASTLeaf *expr = NULL;
akbasic_Token *operator_ = NULL;
PASS(errctx, division(obj, &left));
while ( akbasic_parser_match1(obj, AKBASIC_TOK_STAR) ) {
PASS(errctx, akbasic_parser_previous(obj, &operator_));
PASS(errctx, division(obj, &right));
if ( expr != NULL ) {
left = expr;
}
PASS(errctx, akbasic_parser_new_leaf(obj, &expr));
PASS(errctx, akbasic_leaf_new_binary(expr, left, operator_->tokentype, right));
}
*dest = (expr != NULL ? expr : left);
SUCCEED_RETURN(errctx);
}
static akerr_ErrorContext *division(akbasic_Parser *obj, akbasic_ASTLeaf **dest)
{
PREPARE_ERROR(errctx);
akbasic_ASTLeaf *left = NULL;
akbasic_ASTLeaf *right = NULL;
akbasic_ASTLeaf *expr = NULL;
akbasic_Token *operator_ = NULL;
PASS(errctx, unary(obj, &left));
while ( akbasic_parser_match1(obj, AKBASIC_TOK_LEFT_SLASH) ) {
PASS(errctx, akbasic_parser_previous(obj, &operator_));
PASS(errctx, unary(obj, &right));
if ( expr != NULL ) {
left = expr;
}
PASS(errctx, akbasic_parser_new_leaf(obj, &expr));
PASS(errctx, akbasic_leaf_new_binary(expr, left, operator_->tokentype, right));
}
*dest = (expr != NULL ? expr : left);
SUCCEED_RETURN(errctx);
}
static akerr_ErrorContext *unary(akbasic_Parser *obj, akbasic_ASTLeaf **dest)
{
PREPARE_ERROR(errctx);
akbasic_ASTLeaf *right = NULL;
akbasic_ASTLeaf *expr = NULL;
akbasic_Token *operator_ = NULL;
if ( akbasic_parser_match1(obj, AKBASIC_TOK_MINUS) ) {
PASS(errctx, akbasic_parser_previous(obj, &operator_));
PASS(errctx, akbasic_parser_primary(obj, &right));
PASS(errctx, akbasic_parser_new_leaf(obj, &expr));
PASS(errctx, akbasic_leaf_new_unary(expr, operator_->tokentype, right));
*dest = expr;
SUCCEED_RETURN(errctx);
}
PASS(errctx, exponent(obj, dest));
SUCCEED_RETURN(errctx);
}
static akerr_ErrorContext *exponent(akbasic_Parser *obj, akbasic_ASTLeaf **dest)
{
PREPARE_ERROR(errctx);
akbasic_ASTLeaf *left = NULL;
akbasic_ASTLeaf *right = NULL;
akbasic_ASTLeaf *expr = NULL;
akbasic_Token *operator_ = NULL;
PASS(errctx, function_call(obj, &left));
/*
* Loops for the same reason subtraction does -- `2 ^ 3 ^ 2` abandoned the
* second operator before this. Left-associative, which is a C128: 2^3^2 is
* 64 there, not the 512 a right-associative reading gives.
*/
while ( akbasic_parser_match1(obj, AKBASIC_TOK_CARAT) ) {
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
PASS(errctx, akbasic_parser_previous(obj, &operator_));
PASS(errctx, function_call(obj, &right));
if ( expr != NULL ) {
left = expr;
}
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
PASS(errctx, akbasic_parser_new_leaf(obj, &expr));
PASS(errctx, akbasic_leaf_new_binary(expr, left, operator_->tokentype, right));
}
*dest = (expr != NULL ? expr : left);
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
SUCCEED_RETURN(errctx);
}
/* Count the arguments hanging off an argument list. */
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
static int arglist_length(akbasic_ASTLeaf *arglist)
{
akbasic_ASTLeaf *leaf = NULL;
int count = 0;
if ( arglist == NULL ) {
return 0;
}
for ( leaf = arglist->right; leaf != NULL; leaf = leaf->next ) {
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
count += 1;
}
return count;
}
/*
* Called for function *calls* only, never for a DEF. A FUNCTION token is either
* a table builtin or a user DEF; both check their argument count here, so a
* wrong-arity call is a parse error rather than a runtime surprise.
*/
static akerr_ErrorContext *function_call(akbasic_Parser *obj, akbasic_ASTLeaf **dest)
{
PREPARE_ERROR(errctx);
akbasic_ASTLeaf *arglist = NULL;
akbasic_ASTLeaf *leaf = NULL;
akbasic_Token *operator_ = NULL;
const akbasic_Verb *verb = NULL;
akbasic_FunctionDef *fndef = NULL;
void *fnptr = NULL;
char fname[AKBASIC_MAX_LINE_LENGTH];
int wanted = 0;
int given = 0;
bool found = false;
if ( !akbasic_parser_match1(obj, AKBASIC_TOK_FUNCTION) ) {
PASS(errctx, akbasic_parser_primary(obj, dest));
SUCCEED_RETURN(errctx);
}
PASS(errctx, akbasic_parser_previous(obj, &operator_));
strncpy(fname, operator_->lexeme, sizeof(fname) - 1);
fname[sizeof(fname) - 1] = '\0';
PASS(errctx, akbasic_verb_lookup(fname, &verb));
if ( verb != NULL && verb->tokentype == AKBASIC_TOK_FUNCTION ) {
wanted = verb->arity;
found = true;
} else {
ATTEMPT {
CATCH(errctx, akbasic_environment_get_function(obj->runtime->environment, fname, &fnptr));
found = true;
} CLEANUP {
} PROCESS(errctx) {
} HANDLE(errctx, AKERR_KEY) {
found = false;
} FINISH(errctx, true);
if ( found ) {
fndef = (akbasic_FunctionDef *)fnptr;
wanted = arglist_length(fndef->arglist);
}
}
FAIL_ZERO_RETURN(errctx, found, AKBASIC_ERR_UNDEFINED, "No such function %s", fname);
PASS(errctx, akbasic_parser_argument_list(obj, AKBASIC_TOK_FUNCTION_ARGUMENT, true, &arglist));
given = arglist_length(arglist);
FAIL_ZERO_RETURN(errctx, (given == wanted), AKBASIC_ERR_SYNTAX,
"function %s takes %d arguments, received %d", fname, wanted, given);
PASS(errctx, akbasic_parser_new_leaf(obj, &leaf));
PASS(errctx, akbasic_leaf_new_function(leaf, fname, arglist));
*dest = leaf;
SUCCEED_RETURN(errctx);
}
Add records: TYPE, DIM ... AS, field access, copy on assign BASIC 7.0 has no records at all, so none of this is a port. The `@` suffix was not invented either: the Go reference reserved IDENTIFIER_STRUCT and never used it, and src/grammar.c rendered such a leaf as "NOT IMPLEMENTED" until now. Declaring the type is what buys the storage model. A TYPE states its fields, so an instance has a known slot count and is laid out exactly as an array is -- one contiguous run from the same value pool DIM already draws from, with field access as offset arithmetic. No new pool holds data; the only new table holds descriptors. A nested value flattens into its container's run, which is why LINE with two POINTs and a string is five slots rather than three. Each field takes its type from its own suffix, the same rule every other name here follows, so a field list needs no type column. An `@` field is the exception and has to name its type, because three primitive types fit in three suffix characters and N declared types do not fit in one. The declaration is prescanned before the program runs, like labels and DATA and for the same reason: it has to be in effect wherever control goes. Three passes, each for a case the one before cannot do -- names first so a field can refer to a type declared later, then field lists, then sizes by repeated resolution. What never resolves is a cycle of by-value containment, so "a TYPE cannot contain itself by value" is a diagnosis rather than an assumption, and the message says to use PTR TO instead. Assignment copies. That interception is the whole feature and it cannot live in akbasic_value_clone(), which copies one slot -- and one slot holds a *reference* to an instance rather than the instance, so going through it would alias. A structure is intercepted before that path and its slots are copied one at a time, walking the descriptor rather than memcpy-ing the run, because a pointer field must copy its reference where a value field must copy its slots. Two smaller things the work required. All three prescans now sit inside one ATTEMPT: a malformed declaration is the program's mistake, and it was printing a stack trace and taking the driver with it, which is the boundary goal 3 exists to draw. And a fresh variable's structtype is -1 rather than the 0 a memset leaves, because 0 is a valid type index and every new variable was claiming to be the first type declared. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-08-01 11:39:47 -04:00
/**
* @brief Consume a run of `.field` and `->field` after a primary.
*
* Left-associative, so `A@.B@.C#` reads as `(A@.B@).C#` and each step's base is
* the leaf before it. The two operators are kept apart all the way to the
* runtime rather than folded into one "field access", because which one was
* written is the whole of the strict-pointer rule: `.` requires a structure and
* `->` requires a pointer to one, and getting it wrong is an error rather than a
* convenience the interpreter silently absorbs.
*/
static akerr_ErrorContext *parse_field_chain(akbasic_Parser *obj, akbasic_ASTLeaf **expr)
{
PREPARE_ERROR(errctx);
static const akbasic_TokenType ACCESSORS[] = { AKBASIC_TOK_DOT, AKBASIC_TOK_ARROW };
/*
* A field name carries its own type suffix, exactly as a variable does, so
* the four suffixed identifier tokens are the whole set. A bare identifier
* is not among them: that spelling is a label everywhere else and a field
* with no suffix would have no type.
*/
static const akbasic_TokenType FIELDNAMES[] = {
AKBASIC_TOK_IDENTIFIER_INT, AKBASIC_TOK_IDENTIFIER_FLOAT,
AKBASIC_TOK_IDENTIFIER_STRING, AKBASIC_TOK_IDENTIFIER_STRUCT
};
akbasic_ASTLeaf *field = NULL;
akbasic_Token *accessor = NULL;
akbasic_Token *name = NULL;
akbasic_TokenType op = AKBASIC_TOK_DOT;
while ( akbasic_parser_match(obj, ACCESSORS, 2) ) {
PASS(errctx, akbasic_parser_previous(obj, &accessor));
op = accessor->tokentype;
FAIL_ZERO_RETURN(errctx, akbasic_parser_match(obj, FIELDNAMES, 4), AKBASIC_ERR_SYNTAX,
"Expected a field name after %s", (op == AKBASIC_TOK_ARROW ? "->" : "."));
PASS(errctx, akbasic_parser_previous(obj, &name));
PASS(errctx, akbasic_parser_new_leaf(obj, &field));
PASS(errctx, akbasic_leaf_new_field(field, *expr, name->lexeme, op));
/*
* A field may itself be an array element -- `E@.DROPS#(2)` -- and the
* subscript list belongs to the field, not to the base, so it is
* collected here and onto the field leaf's own `.expr`.
*/
PASS(errctx, akbasic_parser_argument_list(obj, AKBASIC_TOK_ARRAY_SUBSCRIPT, true, &field->expr));
*expr = field;
}
SUCCEED_RETURN(errctx);
}
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
akerr_ErrorContext *akbasic_parser_primary(akbasic_Parser *obj, akbasic_ASTLeaf **dest)
{
PREPARE_ERROR(errctx);
static const akbasic_TokenType PRIMARIES[] = {
AKBASIC_TOK_LITERAL_INT, AKBASIC_TOK_LITERAL_FLOAT, AKBASIC_TOK_LITERAL_STRING,
AKBASIC_TOK_IDENTIFIER, AKBASIC_TOK_IDENTIFIER_STRING, AKBASIC_TOK_IDENTIFIER_FLOAT,
Add records: TYPE, DIM ... AS, field access, copy on assign BASIC 7.0 has no records at all, so none of this is a port. The `@` suffix was not invented either: the Go reference reserved IDENTIFIER_STRUCT and never used it, and src/grammar.c rendered such a leaf as "NOT IMPLEMENTED" until now. Declaring the type is what buys the storage model. A TYPE states its fields, so an instance has a known slot count and is laid out exactly as an array is -- one contiguous run from the same value pool DIM already draws from, with field access as offset arithmetic. No new pool holds data; the only new table holds descriptors. A nested value flattens into its container's run, which is why LINE with two POINTs and a string is five slots rather than three. Each field takes its type from its own suffix, the same rule every other name here follows, so a field list needs no type column. An `@` field is the exception and has to name its type, because three primitive types fit in three suffix characters and N declared types do not fit in one. The declaration is prescanned before the program runs, like labels and DATA and for the same reason: it has to be in effect wherever control goes. Three passes, each for a case the one before cannot do -- names first so a field can refer to a type declared later, then field lists, then sizes by repeated resolution. What never resolves is a cycle of by-value containment, so "a TYPE cannot contain itself by value" is a diagnosis rather than an assumption, and the message says to use PTR TO instead. Assignment copies. That interception is the whole feature and it cannot live in akbasic_value_clone(), which copies one slot -- and one slot holds a *reference* to an instance rather than the instance, so going through it would alias. A structure is intercepted before that path and its slots are copied one at a time, walking the descriptor rather than memcpy-ing the run, because a pointer field must copy its reference where a value field must copy its slots. Two smaller things the work required. All three prescans now sit inside one ATTEMPT: a malformed declaration is the program's mistake, and it was printing a stack trace and taking the driver with it, which is the boundary goal 3 exists to draw. And a fresh variable's structtype is -1 rather than the 0 a memset leaves, because 0 is a valid type index and every new variable was claiming to be the first type declared. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-08-01 11:39:47 -04:00
AKBASIC_TOK_IDENTIFIER_INT, AKBASIC_TOK_FUNCTION, AKBASIC_TOK_IDENTIFIER_STRUCT
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
};
akbasic_ASTLeaf *expr = NULL;
akbasic_ASTLeaf *groupexpr = NULL;
akbasic_Token *previous = NULL;
Add records: TYPE, DIM ... AS, field access, copy on assign BASIC 7.0 has no records at all, so none of this is a port. The `@` suffix was not invented either: the Go reference reserved IDENTIFIER_STRUCT and never used it, and src/grammar.c rendered such a leaf as "NOT IMPLEMENTED" until now. Declaring the type is what buys the storage model. A TYPE states its fields, so an instance has a known slot count and is laid out exactly as an array is -- one contiguous run from the same value pool DIM already draws from, with field access as offset arithmetic. No new pool holds data; the only new table holds descriptors. A nested value flattens into its container's run, which is why LINE with two POINTs and a string is five slots rather than three. Each field takes its type from its own suffix, the same rule every other name here follows, so a field list needs no type column. An `@` field is the exception and has to name its type, because three primitive types fit in three suffix characters and N declared types do not fit in one. The declaration is prescanned before the program runs, like labels and DATA and for the same reason: it has to be in effect wherever control goes. Three passes, each for a case the one before cannot do -- names first so a field can refer to a type declared later, then field lists, then sizes by repeated resolution. What never resolves is a cycle of by-value containment, so "a TYPE cannot contain itself by value" is a diagnosis rather than an assumption, and the message says to use PTR TO instead. Assignment copies. That interception is the whole feature and it cannot live in akbasic_value_clone(), which copies one slot -- and one slot holds a *reference* to an instance rather than the instance, so going through it would alias. A structure is intercepted before that path and its slots are copied one at a time, walking the descriptor rather than memcpy-ing the run, because a pointer field must copy its reference where a value field must copy its slots. Two smaller things the work required. All three prescans now sit inside one ATTEMPT: a malformed declaration is the program's mistake, and it was printing a stack trace and taking the driver with it, which is the boundary goal 3 exists to draw. And a fresh variable's structtype is -1 rather than the 0 a memset leaves, because 0 is a valid type index and every new variable was claiming to be the first type declared. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-08-01 11:39:47 -04:00
if ( akbasic_parser_match(obj, PRIMARIES, 9) ) {
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
PASS(errctx, akbasic_parser_previous(obj, &previous));
PASS(errctx, akbasic_parser_new_leaf(obj, &expr));
switch ( previous->tokentype ) {
case AKBASIC_TOK_LITERAL_INT:
PASS(errctx, akbasic_leaf_new_literal_int(expr, previous->lexeme));
break;
case AKBASIC_TOK_LITERAL_FLOAT:
PASS(errctx, akbasic_leaf_new_literal_float(expr, previous->lexeme));
break;
case AKBASIC_TOK_LITERAL_STRING:
PASS(errctx, akbasic_leaf_new_literal_string(expr, previous->lexeme));
break;
case AKBASIC_TOK_IDENTIFIER_INT:
PASS(errctx, akbasic_leaf_new_identifier(expr, AKBASIC_LEAF_IDENTIFIER_INT, previous->lexeme));
PASS(errctx, akbasic_parser_argument_list(obj, AKBASIC_TOK_ARRAY_SUBSCRIPT, true, &expr->expr));
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
break;
case AKBASIC_TOK_IDENTIFIER_FLOAT:
PASS(errctx, akbasic_leaf_new_identifier(expr, AKBASIC_LEAF_IDENTIFIER_FLOAT, previous->lexeme));
PASS(errctx, akbasic_parser_argument_list(obj, AKBASIC_TOK_ARRAY_SUBSCRIPT, true, &expr->expr));
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
break;
case AKBASIC_TOK_IDENTIFIER_STRING:
PASS(errctx, akbasic_leaf_new_identifier(expr, AKBASIC_LEAF_IDENTIFIER_STRING, previous->lexeme));
PASS(errctx, akbasic_parser_argument_list(obj, AKBASIC_TOK_ARRAY_SUBSCRIPT, true, &expr->expr));
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
break;
Add records: TYPE, DIM ... AS, field access, copy on assign BASIC 7.0 has no records at all, so none of this is a port. The `@` suffix was not invented either: the Go reference reserved IDENTIFIER_STRUCT and never used it, and src/grammar.c rendered such a leaf as "NOT IMPLEMENTED" until now. Declaring the type is what buys the storage model. A TYPE states its fields, so an instance has a known slot count and is laid out exactly as an array is -- one contiguous run from the same value pool DIM already draws from, with field access as offset arithmetic. No new pool holds data; the only new table holds descriptors. A nested value flattens into its container's run, which is why LINE with two POINTs and a string is five slots rather than three. Each field takes its type from its own suffix, the same rule every other name here follows, so a field list needs no type column. An `@` field is the exception and has to name its type, because three primitive types fit in three suffix characters and N declared types do not fit in one. The declaration is prescanned before the program runs, like labels and DATA and for the same reason: it has to be in effect wherever control goes. Three passes, each for a case the one before cannot do -- names first so a field can refer to a type declared later, then field lists, then sizes by repeated resolution. What never resolves is a cycle of by-value containment, so "a TYPE cannot contain itself by value" is a diagnosis rather than an assumption, and the message says to use PTR TO instead. Assignment copies. That interception is the whole feature and it cannot live in akbasic_value_clone(), which copies one slot -- and one slot holds a *reference* to an instance rather than the instance, so going through it would alias. A structure is intercepted before that path and its slots are copied one at a time, walking the descriptor rather than memcpy-ing the run, because a pointer field must copy its reference where a value field must copy its slots. Two smaller things the work required. All three prescans now sit inside one ATTEMPT: a malformed declaration is the program's mistake, and it was printing a stack trace and taking the driver with it, which is the boundary goal 3 exists to draw. And a fresh variable's structtype is -1 rather than the 0 a memset leaves, because 0 is a valid type index and every new variable was claiming to be the first type declared. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-08-01 11:39:47 -04:00
case AKBASIC_TOK_IDENTIFIER_STRUCT:
PASS(errctx, akbasic_leaf_new_identifier(expr, AKBASIC_LEAF_IDENTIFIER_STRUCT, previous->lexeme));
PASS(errctx, akbasic_parser_argument_list(obj, AKBASIC_TOK_ARRAY_SUBSCRIPT, true, &expr->expr));
break;
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
case AKBASIC_TOK_FUNCTION:
case AKBASIC_TOK_IDENTIFIER:
PASS(errctx, akbasic_leaf_new_identifier(expr, AKBASIC_LEAF_IDENTIFIER, previous->lexeme));
break;
default:
FAIL_RETURN(errctx, AKBASIC_ERR_SYNTAX, "Invalid literal type, command or function name");
}
Add records: TYPE, DIM ... AS, field access, copy on assign BASIC 7.0 has no records at all, so none of this is a port. The `@` suffix was not invented either: the Go reference reserved IDENTIFIER_STRUCT and never used it, and src/grammar.c rendered such a leaf as "NOT IMPLEMENTED" until now. Declaring the type is what buys the storage model. A TYPE states its fields, so an instance has a known slot count and is laid out exactly as an array is -- one contiguous run from the same value pool DIM already draws from, with field access as offset arithmetic. No new pool holds data; the only new table holds descriptors. A nested value flattens into its container's run, which is why LINE with two POINTs and a string is five slots rather than three. Each field takes its type from its own suffix, the same rule every other name here follows, so a field list needs no type column. An `@` field is the exception and has to name its type, because three primitive types fit in three suffix characters and N declared types do not fit in one. The declaration is prescanned before the program runs, like labels and DATA and for the same reason: it has to be in effect wherever control goes. Three passes, each for a case the one before cannot do -- names first so a field can refer to a type declared later, then field lists, then sizes by repeated resolution. What never resolves is a cycle of by-value containment, so "a TYPE cannot contain itself by value" is a diagnosis rather than an assumption, and the message says to use PTR TO instead. Assignment copies. That interception is the whole feature and it cannot live in akbasic_value_clone(), which copies one slot -- and one slot holds a *reference* to an instance rather than the instance, so going through it would alias. A structure is intercepted before that path and its slots are copied one at a time, walking the descriptor rather than memcpy-ing the run, because a pointer field must copy its reference where a value field must copy its slots. Two smaller things the work required. All three prescans now sit inside one ATTEMPT: a malformed declaration is the program's mistake, and it was printing a stack trace and taking the driver with it, which is the boundary goal 3 exists to draw. And a fresh variable's structtype is -1 rather than the 0 a memset leaves, because 0 is a valid type index and every new variable was claiming to be the first type declared. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-08-01 11:39:47 -04:00
PASS(errctx, parse_field_chain(obj, &expr));
Port the BASIC interpreter from Go to C Reproduces deps/basicinterpret in C, in the idiom of the ak* libraries. All 41 .bas files in the reference's corpus produce byte-identical stdout, including the trailing double newline on an error line -- that comes from basicError building a string ending in \n and handing it to Println, and array_outofbounds.txt encodes it. The corpus is driven in place from the submodule as 41 individual CTest cases rather than copied, so it cannot drift from upstream. Eighteen unit tests cover what the corpus cannot reach. Three structural changes carry most of the work. Go's three reflection lookups (Command*, Function*, ParseCommand*) become one sorted dispatch table in src/verbs.c searched with bsearch; adding a verb is a row and two functions. The five Go maps become one fixed open-addressed table over aksl_strhash_djb2. And run(), which owned the process until MODE_QUIT, splits into step() plus a bounded run() -- goal 3 requires a host game to be able to bound execution, and nothing in the library now terminates the process or touches SDL. Output goes through an akbasic_TextSink vtable. src/sink_stdio.c is what makes the corpus runnable with no SDL present; the akgl-backed sink is still to come and is blocked on libakgl having no text-measurement call. src/convert.c exists because libakstdlib's aksl_ato* family cannot report a conversion failure (its TODO.md 2.1.5). The reference checks strconv's error at four sites and turns it into a BASIC error; routing those through aksl_atoi would have turned four diagnosable errors into wrong answers, with VAL("garbage") quietly returning 0. TODO.md 1.9 records which libakstdlib calls are cleared for use here and which are not. Reference defects are reproduced, not fixed: the golden files encode the observed behaviour and a silent correction is a behaviour change. TODO.md section 6 lists sixteen, and tests/known_reference_defects.c asserts the *correct* contract for six of them under AKBASIC_KNOWN_FAILING_TESTS, so a fix shows up as "unexpectedly passed". Five of the sixteen were found by this port and are new: subtraction stops after one operator so 1-2-3 computes 1-2 and abandons the rest of the line (a wrong answer, not a refused one); a unary-minus argument inflates a function's arity so ABS(-9) is rejected; a comparison operator in a line's final column is dropped; hex literals never survive the scanner; and the "Reserved word in variable name" check is dead code. Where the reference reaches undefined behaviour by a route that is defined in Go -- an out-of-range shift, a negative string multiplier, integer division by zero -- this raises instead of inheriting the UB. No golden case exercises any of them. The top-level CMakeLists shadows add_test, set_tests_properties and add_custom_target around all three add_subdirectory calls. Without it libakerror's tests land in our suite as Not Run, and its un-namespaced `coverage` target stops a coverage build from configuring at all. Test targets are akbasic_test_<name>: bare test_<name> collides with libakstdlib's, which is what broke libakgl's configure in c2b16d3. ctest 59/59; ASan+UBSan 59/59; 92.3% line and 96.9% function coverage; no warnings under -Wall -Wextra. Branch coverage is not a target, for the reason libakstdlib and libakgl both record: the akerror macros expand into large branch trees at every call site. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 23:53:56 -04:00
*dest = expr;
SUCCEED_RETURN(errctx);
}
if ( akbasic_parser_match1(obj, AKBASIC_TOK_LEFT_PAREN) ) {
PASS(errctx, akbasic_parser_expression(obj, &groupexpr));
PASS(errctx, consume(obj, AKBASIC_TOK_RIGHT_PAREN, "Missing ) after expression"));
PASS(errctx, akbasic_parser_new_leaf(obj, &expr));
PASS(errctx, akbasic_leaf_new_grouping(expr, groupexpr));
*dest = expr;
SUCCEED_RETURN(errctx);
}
PASS(errctx, akbasic_parser_error(obj, "Expected expression or literal"));
SUCCEED_RETURN(errctx);
}