lasercutter: src/clojure/lang/Delay.java annotate

added clojure source goodness

rev	line source
rlm@10	1 /**
rlm@10	2 * Copyright (c) Rich Hickey. All rights reserved.
rlm@10	3 * The use and distribution terms for this software are covered by the
rlm@10	4 * Eclipse Public License 1.0 (http://opensource.org/licenses/eclipse-1.0.php)
rlm@10	5 * which can be found in the file epl-v10.html at the root of this distribution.
rlm@10	6 * By using this software in any fashion, you are agreeing to be bound by
rlm@10	7 * the terms of this license.
rlm@10	8 * You must not remove this notice, or any other, from this software.
rlm@10	9 **/
rlm@10	10
rlm@10	11 /* rich Jun 28, 2007 */
rlm@10	12
rlm@10	13 package clojure.lang;
rlm@10	14
rlm@10	15 public class Delay implements IDeref{
rlm@10	16 Object val;
rlm@10	17 IFn fn;
rlm@10	18
rlm@10	19 public Delay(IFn fn){
rlm@10	20 this.fn = fn;
rlm@10	21 this.val = null;
rlm@10	22 }
rlm@10	23
rlm@10	24 static public Object force(Object x) throws Exception{
rlm@10	25 return (x instanceof Delay) ?
rlm@10	26 ((Delay) x).deref()
rlm@10	27 : x;
rlm@10	28 }
rlm@10	29
rlm@10	30 synchronized public Object deref() throws Exception{
rlm@10	31 if(fn != null)
rlm@10	32 {
rlm@10	33 val = fn.invoke();
rlm@10	34 fn = null;
rlm@10	35 }
rlm@10	36 return val;
rlm@10	37 }
rlm@10	38 }

Mercurial > lasercutter