diff -r f04b33ce250f -r a4dc62a46ee4 Sum.thy --- a/Sum.thy Tue Oct 24 14:59:17 1995 +0100 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,51 +0,0 @@ -(* Title: HOL/Sum.thy - ID: $Id$ - Author: Lawrence C Paulson, Cambridge University Computer Laboratory - Copyright 1992 University of Cambridge - -The disjoint sum of two types. -*) - -Sum = Prod + - -(* type definition *) - -consts - Inl_Rep :: "['a, 'a, 'b, bool] => bool" - Inr_Rep :: "['b, 'a, 'b, bool] => bool" - -defs - Inl_Rep_def "Inl_Rep == (%a. %x y p. x=a & p)" - Inr_Rep_def "Inr_Rep == (%b. %x y p. y=b & ~p)" - -subtype (Sum) - ('a, 'b) "+" (infixr 10) - = "{f. (? a. f = Inl_Rep(a::'a)) | (? b. f = Inr_Rep(b::'b))}" - - -(* abstract constants and syntax *) - -consts - Inl :: "'a => 'a + 'b" - Inr :: "'b => 'a + 'b" - sum_case :: "['a => 'c, 'b => 'c, 'a + 'b] => 'c" - - (*disjoint sum for sets; the operator + is overloaded with wrong type!*) - "plus" :: "['a set, 'b set] => ('a + 'b) set" (infixr 65) - Part :: "['a set, 'b => 'a] => 'a set" - -translations - "case p of Inl(x) => a | Inr(y) => b" == "sum_case(%x.a, %y.b, p)" - -defs - Inl_def "Inl == (%a. Abs_Sum(Inl_Rep(a)))" - Inr_def "Inr == (%b. Abs_Sum(Inr_Rep(b)))" - sum_case_def "sum_case(f, g, p) == @z. (!x. p=Inl(x) --> z=f(x)) - & (!y. p=Inr(y) --> z=g(y))" - - sum_def "A plus B == (Inl``A) Un (Inr``B)" - - (*for selecting out the components of a mutually recursive definition*) - Part_def "Part(A, h) == A Int {x. ? z. x = h(z)}" - -end