src/HOLCF/ex/Loop.thy
author nipkow
Wed, 26 Jul 2000 19:43:28 +0200
changeset 9448 755330e55e18
parent 2642 3c3a84cc85a9
child 10835 f4745d77e620
permissions -rw-r--r--
While functional for defining tail-recursive functions

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

Theory for a loop primitive like while
*)

Loop = Tr +

consts
        step  :: "('a -> tr)->('a -> 'a)->'a->'a"
        while :: "('a -> tr)->('a -> 'a)->'a->'a"

defs

  step_def      "step == (LAM b g x. If b`x then g`x else x fi)"
  while_def     "while == (LAM b g. fix`(LAM f x.
                   If b`x then f`(g`x) else x fi))"

end