doc-src/Tutorial/Datatype/lookup
author wenzelm
Sun, 21 May 2000 14:37:17 +0200
changeset 8899 99266fe189a1
parent 5851 15ce4c1c8313
permissions -rw-r--r--
removed is_type_abbr;
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consts   lookup :: ('a,'v)trie => 'a list => 'v option
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primrec "lookup t [] = value t"
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        "lookup t (a#as) = (case assoc (alist t) a of
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                              None => None
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                            | Some at => lookup at as)"