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>
Co-Authored-By: Andrew Kesterson <andrew@aklabs.net>
2026-07-30 23:53:56 -04:00
|
|
|
/**
|
|
|
|
|
* @file environment.c
|
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|
|
* @brief Implements the scope and per-line working state.
|
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|
|
|
*/
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|
|
#include <inttypes.h>
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|
|
|
#include <string.h>
|
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|
|
#include <akerror.h>
|
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|
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#include <akbasic/environment.h>
|
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#include <akbasic/error.h>
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#include <akbasic/runtime.h>
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|
|
akerr_ErrorContext *akbasic_environment_init(akbasic_Environment *obj, akbasic_Runtime *runtime, akbasic_Environment *parent)
|
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|
|
|
{
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|
PREPARE_ERROR(errctx);
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FAIL_ZERO_RETURN(errctx, (obj != NULL), AKERR_NULLPOINTER, "NULL environment in init");
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FAIL_ZERO_RETURN(errctx, (runtime != NULL), AKERR_NULLPOINTER, "NULL runtime in environment init");
|
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PASS(errctx, akbasic_symtab_init(&obj->variables, AKBASIC_MAX_VARIABLES));
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PASS(errctx, akbasic_symtab_init(&obj->functions, AKBASIC_MAX_FUNCTIONS));
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PASS(errctx, akbasic_symtab_init(&obj->labels, AKBASIC_MAX_LABELS));
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obj->parent = parent;
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obj->runtime = runtime;
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obj->forNextVariable = NULL;
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obj->forStepLeaf = NULL;
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|
obj->forToLeaf = NULL;
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obj->loopFirstLine = 0;
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obj->loopExitLine = 0;
|
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>
Co-Authored-By: Andrew Kesterson <andrew@aklabs.net>
2026-07-31 21:50:37 -04:00
|
|
|
obj->exiting = false;
|
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|
|
|
obj->doConditionLeaf = NULL;
|
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|
|
obj->doConditionKind = AKBASIC_LOOPCOND_NONE;
|
|
|
|
|
obj->isDoLoop = 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>
Co-Authored-By: Andrew Kesterson <andrew@aklabs.net>
2026-07-30 23:53:56 -04:00
|
|
|
obj->gosubReturnLine = 0;
|
|
|
|
|
obj->readReturnLine = 0;
|
|
|
|
|
obj->readIdentifierIdx = 0;
|
|
|
|
|
obj->waitingForCommand[0] = '\0';
|
|
|
|
|
obj->errorToken = NULL;
|
|
|
|
|
memset(obj->readIdentifierLeaves, 0, sizeof(obj->readIdentifierLeaves));
|
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>
Co-Authored-By: Andrew Kesterson <andrew@aklabs.net>
2026-07-31 21:50:37 -04:00
|
|
|
obj->doLeafPool.next = 0;
|
|
|
|
|
obj->doLeafPool.capacity = AKBASIC_MAX_CONDITION_LEAVES;
|
|
|
|
|
obj->doLeafPool.leaves = obj->doLeafStorage;
|
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>
Co-Authored-By: Andrew Kesterson <andrew@aklabs.net>
2026-07-30 23:53:56 -04:00
|
|
|
obj->readLeafPool.next = 0;
|
|
|
|
|
obj->readLeafPool.capacity = AKBASIC_MAX_LEAVES;
|
|
|
|
|
obj->readLeafPool.leaves = obj->readLeafStorage;
|
|
|
|
|
|
|
|
|
|
PASS(errctx, akbasic_value_zero(&obj->forStepValue));
|
|
|
|
|
PASS(errctx, akbasic_value_zero(&obj->forToValue));
|
|
|
|
|
PASS(errctx, akbasic_value_zero(&obj->returnValue));
|
|
|
|
|
|
|
|
|
|
if ( obj->parent != NULL ) {
|
|
|
|
|
obj->lineno = obj->parent->lineno;
|
|
|
|
|
obj->nextline = obj->parent->nextline;
|
|
|
|
|
} else {
|
|
|
|
|
obj->lineno = 0;
|
|
|
|
|
obj->nextline = 0;
|
|
|
|
|
}
|
|
|
|
|
obj->nextvalue = 0;
|
|
|
|
|
PASS(errctx, akbasic_environment_zero_parser(obj));
|
|
|
|
|
SUCCEED_RETURN(errctx);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
akerr_ErrorContext *akbasic_environment_zero(akbasic_Environment *obj)
|
|
|
|
|
{
|
|
|
|
|
PREPARE_ERROR(errctx);
|
|
|
|
|
int i = 0;
|
|
|
|
|
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (obj != NULL), AKERR_NULLPOINTER, "NULL environment in zero");
|
|
|
|
|
for ( i = 0; i < AKBASIC_MAX_VALUES; i++ ) {
|
|
|
|
|
PASS(errctx, akbasic_value_init(&obj->values[i]));
|
|
|
|
|
}
|
|
|
|
|
obj->nextvalue = 0;
|
|
|
|
|
SUCCEED_RETURN(errctx);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
akerr_ErrorContext *akbasic_environment_zero_parser(akbasic_Environment *obj)
|
|
|
|
|
{
|
|
|
|
|
PREPARE_ERROR(errctx);
|
|
|
|
|
int i = 0;
|
|
|
|
|
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (obj != NULL), AKERR_NULLPOINTER, "NULL environment in zero_parser");
|
|
|
|
|
for ( i = 0; i < AKBASIC_MAX_LEAVES; i++ ) {
|
|
|
|
|
PASS(errctx, akbasic_leaf_init(&obj->leaves[i], AKBASIC_LEAF_UNDEFINED));
|
|
|
|
|
}
|
|
|
|
|
for ( i = 0; i < AKBASIC_MAX_TOKENS; i++ ) {
|
|
|
|
|
PASS(errctx, akbasic_token_init(&obj->tokens[i]));
|
|
|
|
|
}
|
|
|
|
|
obj->curtoken = 0;
|
|
|
|
|
obj->nexttoken = 0;
|
|
|
|
|
obj->nextleaf = 0;
|
|
|
|
|
SUCCEED_RETURN(errctx);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
akerr_ErrorContext *akbasic_environment_new_value(akbasic_Environment *obj, akbasic_Value **dest)
|
|
|
|
|
{
|
|
|
|
|
PREPARE_ERROR(errctx);
|
|
|
|
|
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (obj != NULL && dest != NULL), AKERR_NULLPOINTER,
|
|
|
|
|
"NULL argument in new_value");
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (obj->nextvalue < AKBASIC_MAX_VALUES), AKBASIC_ERR_BOUNDS,
|
|
|
|
|
"Maximum values per line reached");
|
|
|
|
|
*dest = &obj->values[obj->nextvalue];
|
|
|
|
|
obj->nextvalue += 1;
|
|
|
|
|
SUCCEED_RETURN(errctx);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
akerr_ErrorContext *akbasic_environment_new_leaf(akbasic_Environment *obj, akbasic_ASTLeaf **dest)
|
|
|
|
|
{
|
|
|
|
|
PREPARE_ERROR(errctx);
|
|
|
|
|
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (obj != NULL && dest != NULL), AKERR_NULLPOINTER,
|
|
|
|
|
"NULL argument in new_leaf");
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (obj->nextleaf < AKBASIC_MAX_LEAVES), AKBASIC_ERR_BOUNDS,
|
|
|
|
|
"No more leaves available");
|
|
|
|
|
*dest = &obj->leaves[obj->nextleaf];
|
|
|
|
|
obj->nextleaf += 1;
|
|
|
|
|
SUCCEED_RETURN(errctx);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
akerr_ErrorContext *akbasic_environment_wait_for_command(akbasic_Environment *obj, const char *command)
|
|
|
|
|
{
|
|
|
|
|
PREPARE_ERROR(errctx);
|
|
|
|
|
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (obj != NULL && command != NULL), AKERR_NULLPOINTER,
|
|
|
|
|
"NULL argument in wait_for_command");
|
|
|
|
|
/*
|
|
|
|
|
* The reference panics here. An interpreter library may not take the process
|
|
|
|
|
* with it, so this raises instead -- but it is still a hard failure, because
|
|
|
|
|
* two pending waits in one environment means the block structure is already
|
|
|
|
|
* corrupt.
|
|
|
|
|
*/
|
|
|
|
|
FAIL_NONZERO_RETURN(errctx, (obj->waitingForCommand[0] != '\0'), AKBASIC_ERR_STATE,
|
|
|
|
|
"Can't wait on multiple commands in the same environment : %s",
|
|
|
|
|
obj->waitingForCommand);
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (strlen(command) < sizeof(obj->waitingForCommand)),
|
|
|
|
|
AKBASIC_ERR_BOUNDS, "Command name '%s' is too long to wait on", command);
|
|
|
|
|
strncpy(obj->waitingForCommand, command, sizeof(obj->waitingForCommand) - 1);
|
|
|
|
|
obj->waitingForCommand[sizeof(obj->waitingForCommand) - 1] = '\0';
|
|
|
|
|
SUCCEED_RETURN(errctx);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
bool akbasic_environment_is_waiting_for_any(akbasic_Environment *obj)
|
|
|
|
|
{
|
|
|
|
|
if ( obj == NULL ) {
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
if ( obj->waitingForCommand[0] != '\0' ) {
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
return akbasic_environment_is_waiting_for_any(obj->parent);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
bool akbasic_environment_is_waiting_for(akbasic_Environment *obj, const char *command)
|
|
|
|
|
{
|
|
|
|
|
if ( obj == NULL || command == NULL ) {
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
if ( strcmp(obj->waitingForCommand, command) == 0 ) {
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
return akbasic_environment_is_waiting_for(obj->parent, command);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
akerr_ErrorContext *akbasic_environment_stop_waiting(akbasic_Environment *obj, const char *command)
|
|
|
|
|
{
|
|
|
|
|
PREPARE_ERROR(errctx);
|
|
|
|
|
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (obj != NULL && command != NULL), AKERR_NULLPOINTER,
|
|
|
|
|
"NULL argument in stop_waiting");
|
|
|
|
|
/*
|
|
|
|
|
* The reference ignores `command` and clears unconditionally, which lets an
|
|
|
|
|
* inner block clear an outer block's wait (TODO.md section 12 item 3). The
|
|
|
|
|
* argument is honoured here only to the extent of walking to the environment
|
|
|
|
|
* that is actually waiting for it -- clearing the wrong one outright would
|
|
|
|
|
* change observable control flow, so the search stops at the first match and
|
|
|
|
|
* a miss is silently tolerated, exactly as today.
|
|
|
|
|
*/
|
|
|
|
|
while ( obj != NULL ) {
|
|
|
|
|
if ( strcmp(obj->waitingForCommand, command) == 0 ) {
|
|
|
|
|
obj->waitingForCommand[0] = '\0';
|
|
|
|
|
SUCCEED_RETURN(errctx);
|
|
|
|
|
}
|
|
|
|
|
obj = obj->parent;
|
|
|
|
|
}
|
|
|
|
|
SUCCEED_RETURN(errctx);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
akerr_ErrorContext *akbasic_environment_get_function(akbasic_Environment *obj, const char *fname, void **dest)
|
|
|
|
|
{
|
|
|
|
|
PREPARE_ERROR(errctx);
|
|
|
|
|
char upper[AKBASIC_SYMTAB_MAX_KEY];
|
|
|
|
|
size_t i = 0;
|
|
|
|
|
size_t len = 0;
|
|
|
|
|
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (obj != NULL && fname != NULL && dest != NULL), AKERR_NULLPOINTER,
|
|
|
|
|
"NULL argument in get_function");
|
|
|
|
|
len = strlen(fname);
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (len < sizeof(upper)), AKERR_KEY, "Function '%s' is not defined", fname);
|
|
|
|
|
for ( i = 0; i < len; i++ ) {
|
|
|
|
|
char c = fname[i];
|
|
|
|
|
upper[i] = (char)((c >= 'a' && c <= 'z') ? (c - 'a' + 'A') : c);
|
|
|
|
|
}
|
|
|
|
|
upper[len] = '\0';
|
|
|
|
|
|
|
|
|
|
while ( obj != NULL ) {
|
|
|
|
|
akerr_ErrorContext *found = akbasic_symtab_get(&obj->functions, upper, dest, NULL);
|
|
|
|
|
if ( found == NULL ) {
|
|
|
|
|
SUCCEED_RETURN(errctx);
|
|
|
|
|
}
|
|
|
|
|
found->handled = true;
|
|
|
|
|
IGNORE(akerr_release_error(found));
|
|
|
|
|
obj = obj->parent;
|
|
|
|
|
}
|
|
|
|
|
FAIL_RETURN(errctx, AKERR_KEY, "Function '%s' is not defined", fname);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
akerr_ErrorContext *akbasic_environment_get_label(akbasic_Environment *obj, const char *label, int64_t *dest)
|
|
|
|
|
{
|
|
|
|
|
PREPARE_ERROR(errctx);
|
|
|
|
|
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (obj != NULL && label != NULL && dest != NULL), AKERR_NULLPOINTER,
|
|
|
|
|
"NULL argument in get_label");
|
|
|
|
|
while ( obj != NULL ) {
|
|
|
|
|
akerr_ErrorContext *found = akbasic_symtab_get(&obj->labels, label, NULL, dest);
|
|
|
|
|
if ( found == NULL ) {
|
|
|
|
|
SUCCEED_RETURN(errctx);
|
|
|
|
|
}
|
|
|
|
|
found->handled = true;
|
|
|
|
|
IGNORE(akerr_release_error(found));
|
|
|
|
|
obj = obj->parent;
|
|
|
|
|
}
|
|
|
|
|
FAIL_RETURN(errctx, AKBASIC_ERR_UNDEFINED,
|
|
|
|
|
"Unable to find or create label %s in environment", label);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
akerr_ErrorContext *akbasic_environment_set_label(akbasic_Environment *obj, const char *label, int64_t value)
|
|
|
|
|
{
|
|
|
|
|
PREPARE_ERROR(errctx);
|
|
|
|
|
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (obj != NULL && label != NULL), AKERR_NULLPOINTER,
|
|
|
|
|
"NULL argument in set_label");
|
|
|
|
|
/* Only the top-level environment creates labels. */
|
|
|
|
|
while ( obj != NULL && obj->runtime->environment != obj ) {
|
|
|
|
|
obj = obj->parent;
|
|
|
|
|
}
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (obj != NULL), AKBASIC_ERR_ENVIRONMENT,
|
|
|
|
|
"Unable to create label in orphaned environment");
|
|
|
|
|
PASS(errctx, akbasic_symtab_set(&obj->labels, label, NULL, value));
|
|
|
|
|
SUCCEED_RETURN(errctx);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
akerr_ErrorContext *akbasic_environment_get(akbasic_Environment *obj, const char *varname, akbasic_Variable **dest)
|
|
|
|
|
{
|
|
|
|
|
PREPARE_ERROR(errctx);
|
|
|
|
|
akbasic_Environment *walk = NULL;
|
|
|
|
|
void *slot = NULL;
|
|
|
|
|
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (obj != NULL && varname != NULL && dest != NULL), AKERR_NULLPOINTER,
|
|
|
|
|
"NULL argument in environment get");
|
|
|
|
|
|
|
|
|
|
*dest = NULL;
|
|
|
|
|
for ( walk = obj; walk != NULL; walk = walk->parent ) {
|
|
|
|
|
akerr_ErrorContext *found = akbasic_symtab_get(&walk->variables, varname, &slot, NULL);
|
|
|
|
|
if ( found == NULL ) {
|
|
|
|
|
*dest = (akbasic_Variable *)slot;
|
|
|
|
|
SUCCEED_RETURN(errctx);
|
|
|
|
|
}
|
|
|
|
|
found->handled = true;
|
|
|
|
|
IGNORE(akerr_release_error(found));
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Parents do not create variables for their children: only the currently
|
|
|
|
|
* active environment auto-creates. A miss anywhere else returns NULL without
|
|
|
|
|
* error, which the caller is expected to notice.
|
|
|
|
|
*/
|
|
|
|
|
if ( obj->runtime->environment != obj ) {
|
|
|
|
|
SUCCEED_RETURN(errctx);
|
|
|
|
|
}
|
|
|
|
|
|
2026-07-31 11:53:05 -04:00
|
|
|
PASS(errctx, akbasic_environment_create(obj, varname, dest));
|
|
|
|
|
SUCCEED_RETURN(errctx);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
akerr_ErrorContext *akbasic_environment_create(akbasic_Environment *obj, const char *varname, akbasic_Variable **dest)
|
|
|
|
|
{
|
|
|
|
|
PREPARE_ERROR(errctx);
|
|
|
|
|
akbasic_Variable *variable = NULL;
|
|
|
|
|
int64_t sizes[1] = { 1 };
|
|
|
|
|
void *slot = NULL;
|
|
|
|
|
akerr_ErrorContext *found = NULL;
|
|
|
|
|
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (obj != NULL && varname != NULL && dest != NULL), AKERR_NULLPOINTER,
|
|
|
|
|
"NULL argument in environment create");
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* This scope only. Unlike akbasic_environment_get() there is no walk up the
|
|
|
|
|
* parent chain: the caller has already said *which* scope it means, and
|
|
|
|
|
* finding an outer one would put the variable somewhere other than where it
|
|
|
|
|
* was asked for.
|
|
|
|
|
*/
|
|
|
|
|
*dest = NULL;
|
|
|
|
|
found = akbasic_symtab_get(&obj->variables, varname, &slot, NULL);
|
|
|
|
|
if ( found == NULL ) {
|
|
|
|
|
*dest = (akbasic_Variable *)slot;
|
|
|
|
|
SUCCEED_RETURN(errctx);
|
|
|
|
|
}
|
|
|
|
|
found->handled = true;
|
|
|
|
|
IGNORE(akerr_release_error(found));
|
|
|
|
|
|
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>
Co-Authored-By: Andrew Kesterson <andrew@aklabs.net>
2026-07-30 23:53:56 -04:00
|
|
|
PASS(errctx, akbasic_runtime_new_variable(obj->runtime, &variable));
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (strlen(varname) < sizeof(variable->name)), AKBASIC_ERR_BOUNDS,
|
|
|
|
|
"Variable name '%s' is too long", varname);
|
|
|
|
|
strncpy(variable->name, varname, sizeof(variable->name) - 1);
|
|
|
|
|
variable->name[sizeof(variable->name) - 1] = '\0';
|
|
|
|
|
variable->valuetype = AKBASIC_TYPE_UNDEFINED;
|
|
|
|
|
variable->mutable_ = true;
|
|
|
|
|
PASS(errctx, akbasic_variable_init(variable, &obj->runtime->valuepool, sizes, 1));
|
|
|
|
|
PASS(errctx, akbasic_symtab_set(&obj->variables, varname, variable, 0));
|
|
|
|
|
*dest = variable;
|
|
|
|
|
SUCCEED_RETURN(errctx);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Evaluate an lvalue's subscript list, if it has one, into `subscripts`. A bare
|
|
|
|
|
* identifier yields the single subscript {0}, which is how a scalar is addressed
|
|
|
|
|
* -- every variable is really a one-element array.
|
|
|
|
|
*/
|
|
|
|
|
static akerr_ErrorContext *collect_subscripts(akbasic_Environment *obj, akbasic_ASTLeaf *lval, int64_t *subscripts, int *count)
|
|
|
|
|
{
|
|
|
|
|
PREPARE_ERROR(errctx);
|
|
|
|
|
akbasic_ASTLeaf *expr = NULL;
|
|
|
|
|
akbasic_Value *tval = NULL;
|
|
|
|
|
|
|
|
|
|
*count = 0;
|
2026-07-31 11:58:15 -04:00
|
|
|
if ( lval->expr != NULL &&
|
|
|
|
|
lval->expr->leaftype == AKBASIC_LEAF_ARGUMENTLIST &&
|
|
|
|
|
lval->expr->operator_ == AKBASIC_TOK_ARRAY_SUBSCRIPT ) {
|
|
|
|
|
for ( expr = lval->expr->right; expr != NULL; 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>
Co-Authored-By: Andrew Kesterson <andrew@aklabs.net>
2026-07-30 23:53:56 -04:00
|
|
|
FAIL_ZERO_RETURN(errctx, (*count < AKBASIC_MAX_ARRAY_DEPTH), AKBASIC_ERR_BOUNDS,
|
|
|
|
|
"More than %d array subscripts", AKBASIC_MAX_ARRAY_DEPTH);
|
|
|
|
|
PASS(errctx, akbasic_runtime_evaluate(obj->runtime, expr, &tval));
|
|
|
|
|
FAIL_NONZERO_RETURN(errctx, (tval->valuetype != AKBASIC_TYPE_INTEGER),
|
|
|
|
|
AKBASIC_ERR_TYPE,
|
|
|
|
|
"Array dimensions must evaluate to integer (B)");
|
|
|
|
|
subscripts[*count] = tval->intval;
|
|
|
|
|
*count += 1;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
if ( *count == 0 ) {
|
|
|
|
|
subscripts[0] = 0;
|
|
|
|
|
*count = 1;
|
|
|
|
|
}
|
|
|
|
|
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>
Co-Authored-By: Andrew Kesterson <andrew@aklabs.net>
2026-08-01 11:39:47 -04:00
|
|
|
/**
|
|
|
|
|
* @brief Assign into a field, checking the field's declared type as it goes.
|
|
|
|
|
*
|
|
|
|
|
* The type check is the same one a variable gets, and it comes from the same
|
|
|
|
|
* place: the field's suffix said what it holds when the TYPE was declared. What
|
|
|
|
|
* is different is that a *field* name is checked for existence at all, which a
|
|
|
|
|
* variable name never is -- the set of fields is closed and written down, and
|
|
|
|
|
* akbasic_structtype_field() lists them when one is missed.
|
|
|
|
|
*/
|
|
|
|
|
static akerr_ErrorContext *assign_field(akbasic_Environment *obj, akbasic_ASTLeaf *lval,
|
|
|
|
|
akbasic_Value *rval, akbasic_Value **dest)
|
|
|
|
|
{
|
|
|
|
|
PREPARE_ERROR(errctx);
|
|
|
|
|
akbasic_StructField *field = NULL;
|
|
|
|
|
akbasic_Value *slot = NULL;
|
|
|
|
|
|
|
|
|
|
PASS(errctx, akbasic_struct_resolve(obj->runtime, lval, &field, &slot));
|
|
|
|
|
|
|
|
|
|
switch ( field->kind ) {
|
|
|
|
|
case AKBASIC_FIELD_STRUCT:
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (rval->valuetype == AKBASIC_TYPE_STRUCT), AKBASIC_ERR_TYPE,
|
|
|
|
|
"Incompatible types in assignment to %s", field->name);
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (rval->structtype == field->typeindex), AKBASIC_ERR_TYPE,
|
|
|
|
|
"%s is a %s and cannot be assigned a %s", field->name,
|
|
|
|
|
obj->runtime->structtypes.types[field->typeindex].name,
|
|
|
|
|
obj->runtime->structtypes.types[rval->structtype].name);
|
|
|
|
|
PASS(errctx, akbasic_struct_copy(obj->runtime, field->typeindex, rval->structbase, slot));
|
|
|
|
|
break;
|
|
|
|
|
case AKBASIC_FIELD_POINTER:
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (rval->valuetype == AKBASIC_TYPE_POINTER), AKBASIC_ERR_TYPE,
|
|
|
|
|
"%s is a pointer; POINT it AT a structure rather than assigning one to it",
|
|
|
|
|
field->name);
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (rval->structtype == field->typeindex), AKBASIC_ERR_TYPE,
|
|
|
|
|
"%s points to %s and cannot hold a pointer to %s", field->name,
|
|
|
|
|
obj->runtime->structtypes.types[field->typeindex].name,
|
|
|
|
|
obj->runtime->structtypes.types[rval->structtype].name);
|
|
|
|
|
PASS(errctx, akbasic_value_clone(rval, slot));
|
|
|
|
|
break;
|
|
|
|
|
default:
|
|
|
|
|
if ( field->valuetype == AKBASIC_TYPE_INTEGER && rval->valuetype == AKBASIC_TYPE_FLOAT ) {
|
|
|
|
|
PASS(errctx, akbasic_value_zero(slot));
|
|
|
|
|
slot->valuetype = AKBASIC_TYPE_INTEGER;
|
|
|
|
|
slot->intval = (int64_t)rval->floatval;
|
|
|
|
|
break;
|
|
|
|
|
}
|
|
|
|
|
if ( field->valuetype == AKBASIC_TYPE_FLOAT && rval->valuetype == AKBASIC_TYPE_INTEGER ) {
|
|
|
|
|
PASS(errctx, akbasic_value_zero(slot));
|
|
|
|
|
slot->valuetype = AKBASIC_TYPE_FLOAT;
|
|
|
|
|
slot->floatval = (double)rval->intval;
|
|
|
|
|
break;
|
|
|
|
|
}
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (rval->valuetype == field->valuetype), AKBASIC_ERR_TYPE,
|
|
|
|
|
"Incompatible types in assignment to %s", field->name);
|
|
|
|
|
PASS(errctx, akbasic_value_clone(rval, slot));
|
|
|
|
|
break;
|
|
|
|
|
}
|
|
|
|
|
*dest = slot;
|
|
|
|
|
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>
Co-Authored-By: Andrew Kesterson <andrew@aklabs.net>
2026-07-30 23:53:56 -04:00
|
|
|
akerr_ErrorContext *akbasic_environment_assign(akbasic_Environment *obj, akbasic_ASTLeaf *lval, akbasic_Value *rval, akbasic_Value **dest)
|
|
|
|
|
{
|
|
|
|
|
PREPARE_ERROR(errctx);
|
|
|
|
|
akbasic_Variable *variable = NULL;
|
|
|
|
|
int64_t subscripts[AKBASIC_MAX_ARRAY_DEPTH];
|
|
|
|
|
int subscriptcount = 0;
|
|
|
|
|
akbasic_Value *slot = NULL;
|
|
|
|
|
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (obj != NULL && lval != NULL && rval != NULL && dest != NULL),
|
|
|
|
|
AKERR_NULLPOINTER, "nil pointer");
|
|
|
|
|
|
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>
Co-Authored-By: Andrew Kesterson <andrew@aklabs.net>
2026-08-01 11:39:47 -04:00
|
|
|
/*
|
|
|
|
|
* A field is addressed by walking the chain, not by looking a name up in a
|
|
|
|
|
* scope -- `E@.POS@.X#` names no variable called `X#`. So it is resolved and
|
|
|
|
|
* assigned here, before the by-name lookup the rest of this function does.
|
|
|
|
|
*/
|
|
|
|
|
if ( lval->leaftype == AKBASIC_LEAF_FIELD ) {
|
|
|
|
|
PASS(errctx, assign_field(obj, lval, rval, dest));
|
|
|
|
|
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>
Co-Authored-By: Andrew Kesterson <andrew@aklabs.net>
2026-07-30 23:53:56 -04:00
|
|
|
PASS(errctx, akbasic_environment_get(obj, lval->identifier, &variable));
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (variable != NULL), AKBASIC_ERR_UNDEFINED,
|
|
|
|
|
"Identifier %s is undefined", lval->identifier);
|
|
|
|
|
PASS(errctx, collect_subscripts(obj, lval, subscripts, &subscriptcount));
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Resolve the slot before the type switch. The reference notes that moving
|
|
|
|
|
* this below the switch corrupts the subscript list; here it is simply the
|
|
|
|
|
* clearer order, and the returned pointer is what an assignment expression
|
|
|
|
|
* evaluates to.
|
|
|
|
|
*/
|
|
|
|
|
PASS(errctx, akbasic_variable_get_subscript(variable, subscripts, subscriptcount, &slot));
|
|
|
|
|
|
|
|
|
|
switch ( lval->leaftype ) {
|
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>
Co-Authored-By: Andrew Kesterson <andrew@aklabs.net>
2026-08-01 11:39:47 -04:00
|
|
|
case AKBASIC_LEAF_IDENTIFIER_STRUCT:
|
|
|
|
|
/*
|
|
|
|
|
* **This is the whole of copy-on-assign**, and it has to happen here
|
|
|
|
|
* rather than in akbasic_value_clone(): a clone copies one slot, and one
|
|
|
|
|
* slot holds a *reference* to an instance rather than the instance. Going
|
|
|
|
|
* through clone would therefore alias -- exactly the reference semantics
|
|
|
|
|
* the language does not have -- so a structure is intercepted before it
|
|
|
|
|
* reaches that path and its slots are copied one at a time.
|
|
|
|
|
*
|
|
|
|
|
* A pointer variable is the opposite and takes the clone: copying a
|
|
|
|
|
* pointer copies the reference, which is what makes `POINT` the only way
|
|
|
|
|
* to share and assignment always a copy.
|
|
|
|
|
*/
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (variable->structtype >= 0), AKBASIC_ERR_STATE,
|
|
|
|
|
"%s has not been DIMmed AS a type", lval->identifier);
|
|
|
|
|
if ( variable->ispointer ) {
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (rval->valuetype == AKBASIC_TYPE_POINTER),
|
|
|
|
|
AKBASIC_ERR_TYPE,
|
|
|
|
|
"%s is a pointer; POINT it AT a structure rather than assigning one to it",
|
|
|
|
|
lval->identifier);
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (rval->structtype == variable->structtype),
|
|
|
|
|
AKBASIC_ERR_TYPE,
|
|
|
|
|
"%s points to %s and cannot hold a pointer to %s",
|
|
|
|
|
lval->identifier,
|
|
|
|
|
obj->runtime->structtypes.types[variable->structtype].name,
|
|
|
|
|
obj->runtime->structtypes.types[rval->structtype].name);
|
|
|
|
|
PASS(errctx, akbasic_value_clone(rval, slot));
|
|
|
|
|
break;
|
|
|
|
|
}
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (rval->valuetype == AKBASIC_TYPE_STRUCT), AKBASIC_ERR_TYPE,
|
|
|
|
|
"Incompatible types in variable assignment");
|
|
|
|
|
FAIL_ZERO_RETURN(errctx, (rval->structtype == variable->structtype), AKBASIC_ERR_TYPE,
|
|
|
|
|
"%s is a %s and cannot be assigned a %s",
|
|
|
|
|
lval->identifier,
|
|
|
|
|
obj->runtime->structtypes.types[variable->structtype].name,
|
|
|
|
|
obj->runtime->structtypes.types[rval->structtype].name);
|
|
|
|
|
PASS(errctx, akbasic_struct_copy(obj->runtime, variable->structtype,
|
|
|
|
|
rval->structbase, slot));
|
|
|
|
|
*dest = slot;
|
|
|
|
|
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>
Co-Authored-By: Andrew Kesterson <andrew@aklabs.net>
2026-07-30 23:53:56 -04:00
|
|
|
case AKBASIC_LEAF_IDENTIFIER_INT:
|
|
|
|
|
if ( rval->valuetype == AKBASIC_TYPE_INTEGER ) {
|
|
|
|
|
PASS(errctx, akbasic_variable_set_integer(variable, rval->intval, subscripts, subscriptcount));
|
|
|
|
|
} else if ( rval->valuetype == AKBASIC_TYPE_FLOAT ) {
|
|
|
|
|
PASS(errctx, akbasic_variable_set_integer(variable, (int64_t)rval->floatval, subscripts, subscriptcount));
|
|
|
|
|
} else {
|
|
|
|
|
FAIL_RETURN(errctx, AKBASIC_ERR_TYPE, "Incompatible types in variable assignment");
|
|
|
|
|
}
|
|
|
|
|
break;
|
|
|
|
|
case AKBASIC_LEAF_IDENTIFIER_FLOAT:
|
|
|
|
|
if ( rval->valuetype == AKBASIC_TYPE_INTEGER ) {
|
|
|
|
|
PASS(errctx, akbasic_variable_set_float(variable, (double)rval->intval, subscripts, subscriptcount));
|
|
|
|
|
} else if ( rval->valuetype == AKBASIC_TYPE_FLOAT ) {
|
|
|
|
|
PASS(errctx, akbasic_variable_set_float(variable, rval->floatval, subscripts, subscriptcount));
|
|
|
|
|
} else {
|
|
|
|
|
FAIL_RETURN(errctx, AKBASIC_ERR_TYPE, "Incompatible types in variable assignment");
|
|
|
|
|
}
|
|
|
|
|
break;
|
|
|
|
|
case AKBASIC_LEAF_IDENTIFIER_STRING:
|
|
|
|
|
FAIL_NONZERO_RETURN(errctx, (rval->valuetype != AKBASIC_TYPE_STRING), AKBASIC_ERR_TYPE,
|
|
|
|
|
"Incompatible types in variable assignment");
|
|
|
|
|
PASS(errctx, akbasic_variable_set_string(variable, rval->stringval, subscripts, subscriptcount));
|
|
|
|
|
break;
|
|
|
|
|
default:
|
|
|
|
|
FAIL_RETURN(errctx, AKBASIC_ERR_TYPE, "Invalid assignment");
|
|
|
|
|
}
|
|
|
|
|
variable->valuetype = rval->valuetype;
|
|
|
|
|
*dest = slot;
|
|
|
|
|
SUCCEED_RETURN(errctx);
|
|
|
|
|
}
|