<variable-effect> ( in-var in out-var out -- effect )
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<terminated-effect> ( in out terminated? -- effect )

Vocabulary
effects

Inputs

in-var	a string or f
in	a sequence of strings or string–type pairs
out-var	a string or f
out	a sequence of strings or string–type pairs

Outputs

effect

an effect

Word description
Constructs an effect object like <effect>. If in-var or out-var are not f, they are used as the names of the Stack effect row variables for the inputs and outputs of the effect object.

Examples

USING: effects prettyprint ; f { "a" "b" } f { "c" } <variable-effect> .
( a b -- c )

USING: effects prettyprint ; "x" { "a" "b" } "y" { "c" } <variable-effect> .
( ..x a b -- ..y c )

USING: arrays effects prettyprint ; "y" { "a" { "b" ( ..x -- ..y ) } } "x" { "c" } <variable-effect> .
( ..y a b: ( ..x -- ..y ) -- ..x c )

USING: effects prettyprint ; "." { "a" "b" } f { "*" } <variable-effect> .
( ... a b -- * )

See also
<effect>, <terminated-effect>

Definition

USING: kernel ;

IN: effects

: <variable-effect> ( in-var in out-var out -- effect )
    swap rotd [ ?terminated ] 2dip effect boa ;