2if ( ..a x y pred: ( ..a x y -- ..b x y ? ) true: ( ..b x y -- ..c ) false: ( ..b x y -- ..c ) -- ..c )
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Vocabulary
kernel

Inputs

x	an object
y	an object
pred	a quotation
true	a quotation
false	a quotation

Outputs
None

Word description
A variant of if that takes a pred quotation. Calls 2check on the pred quotation to return a boolean and preserves x and y for the true or false branches, one of which is called.

See also
1if, 1when, 1unless, 2when, 2unless, 3if, 3when, 3unless

Definition

IN: kernel

: 2if
    ( ..a x y pred: ( ..a x y -- ..b x y ? ) true: ( ..b x y -- ..c ) false: ( ..b x y -- ..c ) -- ..c )
    [ 2check ] 2dip if ; inline