jameysharp opened PR #5663 from no-multi-prio
to main
:
In multi-terms, all matching rules fire. We treat the result as an unordered set of values, so setting rule priorities is meaningless. We want to prohibit relying on the rule match order in this case.
Also, codegen can produce invalid Rust if rules with different priorities both match against a multi-term. We first documented this symptom in #5647. As far as I can figure, prohibiting rule priorities prevents all possible instances of that bug.
At some point in the future we might decide we want to carefully define semantics for multi-term result ordering, at which point we can revisit this.
jameysharp requested fitzgen for a review on PR #5663.
fitzgen submitted PR review.
fitzgen merged PR #5663.
Last updated: Dec 23 2024 at 13:07 UTC