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(* Title: HOL/Library/ExecutableRat.thy
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ID: $Id$
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Author: Florian Haftmann, TU Muenchen
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*)
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header {* Simple example for executable rational numbers *}
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theory Codegenerator_Rat
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22803
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imports ExecutableRat EfficientNat
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begin
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definition
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foo :: "rat \<Rightarrow> rat \<Rightarrow> rat \<Rightarrow> rat" where
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"foo r s t = (t + s) / t"
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definition
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bar :: "rat \<Rightarrow> rat \<Rightarrow> rat \<Rightarrow> bool" where
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"bar r s t \<longleftrightarrow> (r - s) \<le> t \<or> (s - t) \<le> r"
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definition
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"R1 = Fract 3 7"
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definition
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"R2 = Fract (-7) 5"
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definition
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"R3 = Fract 11 (-9)"
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definition
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"foobar = (foo R1 1 R3, bar R2 0 R3, foo R1 R3 R2)"
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22845
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code_gen foobar in SML in OCaml file - in Haskell file -
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ML {* ROOT.Codegenerator_Rat.foobar *}
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code_module Foo
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contains foobar
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ML {* Foo.foobar *}
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end
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