doc-src/Tutorial/Datatype/lookup
author wenzelm
Sat, 01 Jul 2000 19:49:20 +0200
changeset 9226 cbe6144f0f15
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permissions -rw-r--r--
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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)"