| author | haftmann |
| Wed, 21 Mar 2007 08:07:19 +0100 | |
| changeset 22490 | 1822ec4fcecd |
| parent 19249 | 86c73395c99b |
| child 27015 | f8537d69f514 |
| permissions | -rw-r--r-- |
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(*<*) |
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theory Plus imports Main begin |
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(*>*) |
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text{*\noindent Define the following addition function *}
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consts add :: "nat \<Rightarrow> nat \<Rightarrow> nat" |
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primrec |
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"add m 0 = m" |
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"add m (Suc n) = add (Suc m) n" |
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text{*\noindent and prove*}
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(*<*) |
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lemma [simp]: "!m. add m n = m+n" |
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apply(induct_tac n) |
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by(auto) |
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(*>*) |
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lemma "add m n = m+n" |
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(*<*) |
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by(simp) |
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end |
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(*>*) |