union ( set1 set2 -- set )
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Vocabulary
sets

Inputs

set1	a set
set2	a set

Outputs

set

a set

Word description
Outputs a set consisting of elements present in either set1 or set2 which does not contain duplicate values.

This word has a default definition which works for all sets, but set implementations may override the default for efficiency.

Examples

USING: sets prettyprint ; { 1 2 3 } { 2 3 4 } union .
{ 1 2 3 4 }

See also
diff, intersect

Definition

IN: sets

GENERIC: union ( set1 set2 -- set )

Methods

USING: bit-sets bit-sets.private math sets ;

M: bit-set union [ bitor ] bit-set-op ;


USING: accessors hash-sets hash-sets.private kernel sets
sets.private ;

M: hash-set union
    over hash-set? [
        small/large [ array>> ] [ clone ] bi*
        [ [ adjoin ] curry each-member ] keep
    ] [ (union) >hash-set ] if ;


USING: kernel sets sets.private ;

M: set union [ (union) ] keep set-like ;