src/HOLCF/Tr1.thy
author lcp
Thu, 12 Jan 1995 03:00:58 +0100
changeset 850 a744f9749885
parent 625 119391dd1d59
child 1168 74be52691d62
permissions -rw-r--r--
Added constants Ord_alt, ++, **

(*  Title: 	HOLCF/tr1.thy
    ID:         $Id$
    Author: 	Franz Regensburger
    Copyright   1993 Technische Universitaet Muenchen

Introduce the domain of truth values tr = one ++ one

The type is axiomatized as the least solution of a domain equation.
The functor term that specifies the domain equation is: 

  FT = <++,K_{one},K_{one}>

For details see chapter 5 of:

[Franz Regensburger] HOLCF: Eine konservative Erweiterung von HOL um LCF,
                     Dissertation, Technische Universit"at M"unchen, 1994

*)

Tr1 = One +

types tr 0
arities tr :: pcpo

consts
	abs_tr		:: "one ++ one -> tr"
	rep_tr		:: "tr -> one ++ one"
	TT 		:: "tr"
	FF		:: "tr"
	tr_when 	:: "'c -> 'c -> tr -> 'c"

rules

  abs_tr_iso	"abs_tr[rep_tr[u]] = u"
  rep_tr_iso	"rep_tr[abs_tr[x]] = x"

  TT_def	"TT == abs_tr[sinl[one]]"
  FF_def	"FF == abs_tr[sinr[one]]"

  tr_when_def "tr_when == (LAM e1 e2 t.when[LAM x.e1][LAM y.e2][rep_tr[t]])"

end