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A postfix parser reverses noncommutative operands · case 05
A postfix parser reverses noncommutative operands.
Case contract
Parse a valid postfix token list with binary plus/minus into [operator,left,right] ASTs; letters are leaves.
Why this case matters
A local executable model for consumers of structured text; oracle values are authored literals, not outputs copied from the repaired implementation.
One recorded failure
Sample boundary fixtureThis sample comes from the broken implementation of a controlled reproducer.
| Boundary fixture | Actual | Expected | Outcome |
|---|---|---|---|
| boundary 1 | ["-", "b", "a"] | ["-", "a", "b"] | Failed |
MEMBER ARCHIVE
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This record includes three runnable implementations, regression fixtures, execution results, and source hashes.
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