doc-src/Tutorial/Datatype/lookup
author paulson
Tue, 16 Jan 2001 12:20:52 +0100
changeset 10919 144ede948e58
parent 5851 15ce4c1c8313
permissions -rw-r--r--
renamings: real_of_nat, real_of_int -> (overloaded) real inf_close -> approx SReal -> Reals SNat -> Nats
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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)"