doc-src/Tutorial/Datatype/lookup
author wenzelm
Sun, 13 Feb 2000 20:56:55 +0100
changeset 8235 a4fb9be6b19a
parent 5851 15ce4c1c8313
permissions -rw-r--r--
prf_script commands made proper; removed then_apply; added apply_end;
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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)"