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5851
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1 |
consts update :: ('a,'v)trie => 'a list => 'v => ('a,'v)trie
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2 |
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3 |
primrec
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4 |
"update t [] v = Trie (Some v) (alist t)"
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5 |
"update t (a#as) v = (let tt = (case assoc (alist t) a of
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6 |
None => Trie None [] | Some at => at)
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7 |
in Trie (value t) ((a,update tt as v)#alist t))"
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