maybe-set-of ( assoc key value -- assoc changed? )

Vocabulary

assocs.extras

Inputs

assoc	an object
key	an object
value	an object

Outputs

assoc	an object
changed?	an object

Definition

USING: assocs kernel ;

IN: assocs.extras

: maybe-set-of ( assoc key value -- assoc changed? )
    [ 2dup ?of ] dip swap
    [ dupd = [ 2drop f ] [ set-of t ] if ] [ nip set-of t ] if ;