made empty list non-seq

1 files changed, 26 insertions, 12 deletions

diff --git a/src/jvm/clojure/lang/PersistentList.java b/src/jvm/clojure/lang/PersistentList.java
index cd86b033..9009f016 100644
--- a/src/jvm/clojure/lang/PersistentList.java
+++ b/src/jvm/clojure/lang/PersistentList.java
@@ -17,7 +17,7 @@ import java.util.LinkedList;
 public class PersistentList extends ASeq implements IPersistentList{

 

 private final Object _first;

-private final PersistentList _rest;

+private final IPersistentList _rest;

 private final int _count;

 

 public static IFn creator = new RestFn(0){

@@ -25,9 +25,9 @@ public static IFn creator = new RestFn(0){
 		if(args instanceof ArraySeq)

 			{

 			Object[] argsarray = (Object[]) ((ArraySeq) args).array;

-			ISeq ret = EMPTY;

+			IPersistentList ret = EMPTY;

 			for(int i = argsarray.length - 1; i >= 0; --i)

-				ret = ret.cons(argsarray[i]);

+				ret = (IPersistentList) ret.cons(argsarray[i]);

 			return ret;

 			}

 		LinkedList list = new LinkedList();

@@ -37,7 +37,7 @@ public static IFn creator = new RestFn(0){
 	}

 };

 

-final public static PersistentList EMPTY = new EmptyList(null);

+final public static EmptyList EMPTY = new EmptyList(null);

 

 public PersistentList(Object first){

 	this._first = first;

@@ -46,18 +46,18 @@ public PersistentList(Object first){
 	this._count = 1;

 }

 

-PersistentList(IPersistentMap meta, Object _first, PersistentList _rest, int _count){

+PersistentList(IPersistentMap meta, Object _first, IPersistentList _rest, int _count){

 	super(meta);

 	this._first = _first;

 	this._rest = _rest;

 	this._count = _count;

 }

 

-public static ISeq create(List init){

-	ISeq ret = EMPTY;

+public static IPersistentList create(List init){

+	IPersistentList ret = EMPTY;

 	for(ListIterator i = init.listIterator(init.size()); i.hasPrevious();)

 		{

-		ret = ret.cons(i.previous());

+		ret = (IPersistentList) ret.cons(i.previous());

 		}

 	return ret;

 }

@@ -67,7 +67,9 @@ public Object first(){
 }

 

 public ISeq rest(){

-	return _rest;

+	if(_count == 1)

+		return null;

+	return (ISeq) _rest;

 }

 

 public Object peek(){

@@ -98,26 +100,38 @@ public PersistentList withMeta(IPersistentMap meta){
 	return this;

 }

 

-static class EmptyList extends PersistentList{

+static class EmptyList extends Obj implements IPersistentList{

 

 	EmptyList(IPersistentMap meta){

-		super(meta, null, null, 0);

+		super(meta);

 	}

 

 	public PersistentList cons(Object o){

 		return new PersistentList(meta(), o, null, 1);

 	}

 

-	public PersistentList withMeta(IPersistentMap meta){

+	public IPersistentCollection empty(){

+		return this;

+	}

+

+	public EmptyList withMeta(IPersistentMap meta){

 		if(meta != meta())

 			return new EmptyList(meta);

 		return this;

 	}

 

+	public Object peek(){

+		return null;

+	}

+

 	public IPersistentList pop(){

 		throw new IllegalStateException("Can't pop empty list");

 	}

 

+	public int count(){

+		return 0;

+	}

+

 	public ISeq seq(){

 		return null;

 	}