doc-src/TutorialI/Misc/Plus.thy
author huffman
Sat, 20 Aug 2011 10:08:47 -0700
changeset 44346 00dd3c4dabe0
parent 27015 f8537d69f514
permissions -rw-r--r--
rename real_squared_diff_one_factored to square_diff_one_factored and move to Rings.thy
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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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primrec add :: "nat \<Rightarrow> nat \<Rightarrow> nat" where
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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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(*>*)