出典:Wikipedia
出典:『Wikipedia』 (2011/07/27 00:28 UTC 版)
In computer science, polymorphism recursion refers to a recursive parametrically polymorph function where the type parameter changes with each recursive invocation made instead of staying constant. Type inference for polymorphic recursion is equivalent to semi-unification and thefore undecidable and requires the use of a semi-algorithm or programmer supplied type annotations.