Only one unparenthesised AND or OR is matched per expression #2

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tachikoma · 2026-08-02T19:04:08-04:00

tachikoma commented

2026-08-02 19:04:08 -04:00

Source: TODO.md §6 item 36 (at 9151438)

A second one is left in the token stream, and in the place a program actually writes them -- a
condition -- the THEN check then finds the wrong token and the line is refused:

X# = 1
Y# = 2
IF X# = 1 AND Y# = 2 THEN PRINT "TWO IS FINE"
IF X# = 1 AND Y# = 2 AND X# = 1 THEN PRINT "THREE IS NOT"

TWO IS FINE
? 4 : PARSE ERROR Incomplete IF statement

Parenthesising is the workaround and it works -- IF (A AND B) AND C THEN parses -- which is what
the tutorials tell a reader to do. It is a refusal rather than a wrong answer, so it costs a
puzzled minute rather than an evening.

logicalandor() (src/parser.c:329) is if ( akbasic_parser_match(obj, OPS, 2) ) at :339
where subtraction() at :425 is while. This is the same defect as the earlier
associativity one, on the one operator pair that fix did not reach, and the Go reference has
the same shape.

The fix is the same fix: while, folding left, reassigning left from the leaf built on the
previous pass. tests/parser_expressions.c for the expression form and tests/parser_commands.c
for the IF that made it visible.

Files: src/parser.c:329,339, tests/parser_expressions.c, tests/parser_commands.c

Filed by Tachikoma (Claude Code, Opus 5, 1M context)

**Source:** TODO.md §6 item 36 (at 9151438) A second one is left in the token stream, and in the place a program actually writes them -- a condition -- the `THEN` check then finds the wrong token and the line is refused: ```basic X# = 1 Y# = 2 IF X# = 1 AND Y# = 2 THEN PRINT "TWO IS FINE" IF X# = 1 AND Y# = 2 AND X# = 1 THEN PRINT "THREE IS NOT" ``` ```output TWO IS FINE ? 4 : PARSE ERROR Incomplete IF statement ``` Parenthesising is the workaround and it works -- `IF (A AND B) AND C THEN` parses -- which is what the tutorials tell a reader to do. **It is a refusal rather than a wrong answer, so it costs a puzzled minute rather than an evening.** `logicalandor()` (`src/parser.c:329`) is `if ( akbasic_parser_match(obj, OPS, 2) )` at `:339` where `subtraction()` at `:425` is `while`. **This is the same defect as the earlier associativity one**, on the one operator pair that fix did not reach, and the Go reference has the same shape. **The fix is the same fix:** `while`, folding left, reassigning `left` from the leaf built on the previous pass. `tests/parser_expressions.c` for the expression form and `tests/parser_commands.c` for the `IF` that made it visible. **Files:** `src/parser.c:329,339`, `tests/parser_expressions.c`, `tests/parser_commands.c` --- Filed by Tachikoma (Claude Code, Opus 5, 1M context)

tachikoma added this to the 0.1.x milestone 2026-08-02 19:04:08 -04:00

tachikoma added the defect blast-radius:high status::grooming labels 2026-08-02 19:04:08 -04:00

tachikoma referenced this issue

2026-08-02 19:08:53 -04:00

Move outstanding work from TODO.md into the issue tracker #27

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