Mercurial > lasercutter

     1 /**

     2  *   Copyright (c) Rich Hickey. All rights reserved.

     3  *   The use and distribution terms for this software are covered by the

     4  *   Eclipse Public License 1.0 (http://opensource.org/licenses/eclipse-1.0.php)

     5  *   which can be found in the file epl-v10.html at the root of this distribution.

     6  *   By using this software in any fashion, you are agreeing to be bound by

     7  * 	 the terms of this license.

     8  *   You must not remove this notice, or any other, from this software.

     9  **/

    10 

    11 /* rich Apr 1, 2008 */

    12 

    13 package clojure.lang;

    14 

    15 public class Range extends ASeq implements IReduce, Counted{

    16 final int end;

    17 final int n;

    18 

    19 public Range(int start, int end){

    20 	this.end = end;

    21 	this.n = start;

    22 }

    23 

    24 public Range(IPersistentMap meta, int start, int end){

    25 	super(meta);

    26 	this.end = end;

    27 	this.n = start;

    28 }

    29 

    30 public Obj withMeta(IPersistentMap meta){

    31 	if(meta == meta())

    32 		return this;

    33 	return new Range(meta(), end, n);

    34 }

    35 

    36 public Object first(){

    37 	return n;

    38 }

    39 

    40 public ISeq next(){

    41 	if(n < end-1)

    42 		return new Range(_meta, n + 1, end);

    43 	return null;

    44 }

    45 

    46 public Object reduce(IFn f) throws Exception{

    47 	Object ret = n;

    48 	for(int x = n+1;x < end;x++)

    49 		ret = f.invoke(ret, x);

    50 	return ret;

    51 }

    52 

    53 public Object reduce(IFn f, Object start) throws Exception{

    54 	Object ret = f.invoke(start,n);

    55 	for(int x = n+1;x < end;x++)

    56 		ret = f.invoke(ret, x);

    57 	return ret;

    58 }

    59 

    60 public int count() {

    61     return end - n;

    62     }

    63 

    64 }
author	Robert McIntyre <rlm@mit.edu>
date	Sat, 21 Aug 2010 06:25:44 -0400
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