Fix match exhaustiveness for Bool value patterns in tuples (#5226)#166
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IgorDeepakM merged 1 commit intomasterfrom Apr 30, 2026
Merged
Fix match exhaustiveness for Bool value patterns in tuples (#5226)#166IgorDeepakM merged 1 commit intomasterfrom
IgorDeepakM merged 1 commit intomasterfrom
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The exhaustiveness checker's existing Bool special-case (tracking seen_true/seen_false) only worked at the top level. Bool literals inside tuples were rejected as non-exhaustive even when both true and false were covered. Introduce internal-only TK_BOOL_TRUE / TK_BOOL_FALSE singleton type tokens that exist only during the is_match_exhaustive check. Both the discriminee type and case types are expanded so that Bool becomes (TK_BOOL_TRUE | TK_BOOL_FALSE), letting the existing tuple-of-union distribution machinery handle exhaustiveness at any nesting depth. Closes #5194
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The exhaustiveness checker's existing Bool special-case (tracking seen_true/seen_false) only worked at the top level. Bool literals inside tuples were rejected as non-exhaustive even when both true and false were covered.
Introduce internal-only TK_BOOL_TRUE / TK_BOOL_FALSE singleton type tokens that exist only during the is_match_exhaustive check. Both the discriminee type and case types are expanded so that Bool becomes (TK_BOOL_TRUE | TK_BOOL_FALSE), letting the existing tuple-of-union distribution machinery handle exhaustiveness at any nesting depth.
Closes #5194