?box ( box -- value/f ? )
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box> ( box -- value )

Vocabulary
boxes

Inputs

box

a box

Outputs

value/f	the value of the box or f
?	a boolean

Word description
If the box is full, removes the value from the box and pushes t. If the box is empty pushes f f.

Definition

USING: accessors boxes.private kernel ;

IN: boxes

: ?box ( box -- value/f ? )
    dup occupied>> [ box-unsafe> t ] [ drop f f ] if ; inline