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doc-src/Tutorial/Datatype/lookup
author paulson
Tue, 18 Apr 2000 15:51:59 +0200
changeset 8736 0bfd6678a5fa
parent 5851 15ce4c1c8313
permissions -rw-r--r--
new simprocs for numerals of type "nat"

consts   lookup :: ('a,'v)trie => 'a list => 'v option
primrec "lookup t [] = value t"
        "lookup t (a#as) = (case assoc (alist t) a of
                              None => None
                            | Some at => lookup at as)"
isabelle