author | kleing |
Sun, 18 May 2003 15:28:41 +0200 | |
changeset 14035 | c46ce87960fb |
parent 13739 | f5d0a66c8124 |
permissions | -rw-r--r-- |
(*<*) theory Snoc = Main: (*>*) subsection {* Lists *} text {* Define a primitive recursive function @{text snoc} that appends an element at the \emph{right} end of a list. Do not use @{text"@"} itself. *} consts snoc :: "'a list => 'a => 'a list" text {* Prove the following theorem: *} theorem rev_cons: "rev (x # xs) = snoc (rev xs) x" (*<*)oops(*>*) text {* Hint: you need to prove a suitable lemma first. *} (*<*) end (*>*)