doc-src/TutorialI/Misc/let_rewr.thy
author nipkow
Wed, 19 Apr 2000 12:54:56 +0200
changeset 8746 ccbb5e0dccdf
parent 8745 13b32661dde4
child 8771 026f37a86ea7
permissions -rw-r--r--
Adding generated files.
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(*<*)
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theory let_rewr = Main:;
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(*>*)
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lemma "(let xs = [] in xs@ys@xs) = ys";
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apply(simp add: Let_def).;
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text{*
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If, in a particular context, there is no danger of a combinatorial explosion
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of nested \texttt{let}s one could even add \texttt{Let_def} permanently:
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*}
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theorems [simp] = Let_def;
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(*<*)
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end
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(*>*)