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doc-src/Tutorial/Datatype/lookup
author wenzelm
Sat, 06 Jan 2001 21:29:29 +0100
changeset 10809 e827c779ae2e
parent 5851 15ce4c1c8313
permissions -rw-r--r--
moved norm_hhf_tac to Pure/tactic.ML; adapted invoke_case;
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
5851
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consts   lookup :: ('a,'v)trie => 'a list => 'v option
15ce4c1c8313 New section on advanced datatypes.
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primrec "lookup t [] = value t"
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        "lookup t (a#as) = (case assoc (alist t) a of
15ce4c1c8313 New section on advanced datatypes.
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                              None => None
15ce4c1c8313 New section on advanced datatypes.
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                            | Some at => lookup at as)"
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