Fix spurious error when assigning to a field on an as cast in a try block#5070
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SeanTAllen wants to merge 1 commit intomainfrom
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Fix spurious error when assigning to a field on an as cast in a try block#5070SeanTAllen wants to merge 1 commit intomainfrom
as cast in a try block#5070SeanTAllen wants to merge 1 commit intomainfrom
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… block The `as` operator desugars to a match with a consume of an internal hygienic variable. The refer pass's `ast_get_child` function searched the entire assignment LHS subtree — including the desugared match's scope — for consumed variable names, producing a false positive that triggered the verify pass error. Stopping the search at scope boundaries prevents descending into match-internal variables that aren't assignment targets. Closes #3604
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Assigning to a field on the result of an
asexpression inside atryblock produced a spurious error about consumed identifiers. Theasoperator desugars to a match with aconsumeof an internal hygienic variable, and the refer pass'sast_get_childfunction searched the entire assignment LHS subtree — including the desugared match's scope — for consumed variable names. This produced a false positive that triggered the verify pass error.The fix stops
ast_get_childfrom recursing into children that introduce their own scope. Variables bound in those scopes (like the match-internal hygienic variable) aren't assignment targets of the outer expression.Closes #3604