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…ion NullReferenceException Test both function-scoped and type-constructor-scoped variants of mutually recursive sequence expressions to verify the NullReferenceException no longer occurs. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Fixes #3783
Summary
Adds a regression test for issue #3783 which reported a
NullReferenceExceptionwhen using mutually recursivelet rec ... andbindings with sequence computation expressions.The issue originally manifested in both:
let rec a = seq { ... } and b () = seq { ... }bindingsBoth variants now compile and run correctly, producing the expected alternating
[0; 1; 0; 1; ...]sequence.Test
The test compiles and executes both variants, asserting the output matches
[0; 1; 0; 1; 0; 1; 0; 1; 0; 1].