The Undecidability of Pattern Matching in Calculi where Primitive Recursive Functions are Representable
We prove that the pattern matching problem is undecidable in polymorphic lambda-calculi (as Girard's system F) and calculi supporting inductive types (as Gödel's system T) by reducing Hilbert's tenth problem to it. More generally pattern matching is undecidable in all the calculi in which primitive recursive functions can be fairly represented in a precised sense.
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