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(* Title: HOLCF/Coind.thy
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ID: $Id$
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Author: Franz Regensburger
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Copyright 1993 Technische Universitaet Muenchen
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Example for co-induction on streams
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*)
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Coind = Stream2 +
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consts
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nats :: "dnat stream"
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from :: "dnat -> dnat stream"
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defs
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nats_def "nats == fix`(LAM h.scons`dzero`(smap`dsucc`h))"
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from_def "from == fix`(LAM h n.scons`n`(h`(dsucc`n)))"
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end
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(*
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smap`f`UU = UU
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x~=UU --> smap`f`(scons`x`xs) = scons`(f`x)`(smap`f`xs)
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nats = scons`dzero`(smap`dsucc`nats)
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from`n = scons`n`(from`(dsucc`n))
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*)
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