<promise> ( quot -- promise )

Vocabulary
promises

Inputs

quot	a quotation with stack effect ( -- x )

Outputs

promise

a promise object

Word description
Creates a promise to return a value. When forced this quotation is called and the value returned. The value is memorised so that calling force again does not call the quotation again, instead the previous value is returned directly.

Definition

USING: kernel ;

IN: promises

: <promise> ( quot -- promise ) f f promise boa ;