assoc-find ( ... assoc quot: ( ... key value -- ... ? ) -- ... key value ? )
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Vocabulary
assocs

Inputs

assoc	an assoc
quot	a quotation with stack effect ( ... key value -- ... ? )

Outputs

key	the successful key, or f
value	the successful value, or f
?	a boolean

Word description
Applies a predicate quotation to each entry in the assoc. Returns the key and value that the quotation succeeds on, or f for both if the quotation fails. It also returns a boolean describing whether there was anything found; this can be used to distinguish between a key and a value equal to f, or nothing being found.

Definition

USING: assocs.private kernel sequences sequences.private ;

IN: assocs

: assoc-find
    ( ... assoc quot: ( ... key value -- ... ? ) -- ... key value ? )
    assoc-operator find swap
    [ first2-unsafe t ] [ drop f f f ] if ; inline