doc-src/TutorialI/Misc/Plus.thy
author chaieb
Wed, 19 May 2004 11:23:59 +0200
changeset 14758 af3b71a46a1c
parent 13305 f88d0c363582
child 16417 9bc16273c2d4
permissions -rw-r--r--
A new implementation for presburger arithmetic following the one suggested in technical report Chaieb Amine and Tobias Nipkow. It is generic an smaller. the tactic has also changed and allows the abstaction over fuction occurences whose type is nat or int.

(*<*)
theory Plus = Main:
(*>*)

text{*\noindent Define the following addition function *}

consts plus :: "nat \<Rightarrow> nat \<Rightarrow> nat"
primrec
"plus m 0 = m"
"plus m (Suc n) = plus (Suc m) n"

text{*\noindent and prove*}
(*<*)
lemma [simp]: "!m. plus m n = m+n"
apply(induct_tac n)
by(auto)
(*>*)
lemma "plus m n = m+n"
(*<*)
by(simp)

end
(*>*)