Standard ML of New Jersey

The SUSP signature

Synopsis

signature SUSP
structure Susp : SUSP


This module creates and manipulates suspensions for lazy evaluation.

Interface

type 'a susp
val delay : (unit -> 'a) -> 'a susp
val force : 'a susp -> 'a


Description

type 'a susp

delay f

Make a suspension from function f.

force s

If s has never been forced before, evaluate its underlying f function, save the result, and return the result. If s has been previously forced, return the result from last time.

Last Modified October 28, 1997
Comments to sml-nj@research.bell-labs.com
Copyright © 1998 Bell Labs, Lucent Technologies