Reduction - free normalisation for system
نویسندگان
چکیده
We present a semantical proof of existence of normal forms for system F including -equality. A reduction-free normalisation function can be obtained from this. The proof uses the method of glueing (a variant of) the term model along the global sections functor, carried out in the internal language of a category of presheaves. As a by-product we obtain an semantical explanation of higherorder abstract syntax. The paper extends a previous one (Altenkirch, Hofmann, and Streicher 1996) in which a combinatory version of system F has been treated.
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