interim checkin, incorporating new stream model

10 files changed, 707 insertions, 795 deletions

diff --git a/src/jvm/clojure/lang/APersistentVector.java b/src/jvm/clojure/lang/APersistentVector.java
index 8a271b6a..a11217e3 100644
--- a/src/jvm/clojure/lang/APersistentVector.java
+++ b/src/jvm/clojure/lang/APersistentVector.java
@@ -405,18 +405,25 @@ public int compareTo(Object o){
 	return 0;
 }
 
-public IStream stream() throws Exception {
-    final AtomicInteger ai = new AtomicInteger(0);
-    return new IStream(){
-        public Object next() throws Exception {
-            int i = ai.getAndIncrement();
-            if(i < count())
-                return nth(i);
-            return RT.eos();
-        }
-    };
+public Stream stream() throws Exception {
+    return new Stream(new Src(this));
 }
 
+    static class Src extends AFn{
+        final IPersistentVector v;
+        int i = 0;
+
+        Src(IPersistentVector v) {
+            this.v = v;
+        }
+
+        public Object invoke() throws Exception {
+            if (i < v.count())
+                return v.nth(i++);
+            return RT.EOS;
+        }
+    }
+
     static class Seq extends ASeq implements IndexedSeq, IReduce{
 	//todo - something more efficient
 	final IPersistentVector v;
diff --git a/src/jvm/clojure/lang/ASeq.java b/src/jvm/clojure/lang/ASeq.java
index 938c55e7..cb38bb6d 100644
--- a/src/jvm/clojure/lang/ASeq.java
+++ b/src/jvm/clojure/lang/ASeq.java
@@ -204,25 +204,26 @@ public Iterator iterator(){
 

 

 

-public IStream stream() throws Exception {

-    return new Stream(this);

+public Stream stream() throws Exception {

+    return new Stream(new Src(this));

 }

 

-    static class Stream implements IStream{

+static class Src extends AFn{

     ISeq s;

 

-    public Stream(ISeq s) {

+    public Src(ISeq s) {

         this.s = s;

     }

 

-    synchronized public Object next() throws Exception {

-        if(s != null)

+	public Object invoke() throws Exception {

+		ISeq sq = RT.seq(s);

+        if(sq != null)

             {

-            Object ret = s.first();

-            s = s.next();

+            Object ret = sq.first();

+            s = sq.more();

             return ret;

             }

-        return RT.eos();

+        return RT.EOS;

     }

 }

 

diff --git a/src/jvm/clojure/lang/ArrayStream.java b/src/jvm/clojure/lang/ArrayStream.java
index 8fadbd94..29750cad 100644
--- a/src/jvm/clojure/lang/ArrayStream.java
+++ b/src/jvm/clojure/lang/ArrayStream.java
@@ -14,181 +14,171 @@ package clojure.lang;
 
 import java.util.concurrent.atomic.AtomicInteger;
 import java.lang.reflect.Array;
+public class ArrayStream extends AFn{
 
-public class ArrayStream implements IStream {
-
-    final AtomicInteger ai = new AtomicInteger(0);
-    final Object[] array;
-
-    public ArrayStream(Object[] array) {
-        this.array = array;
-    }
-
-    public Object next() throws Exception {
-        int i = ai.getAndIncrement();
-        if (i < array.length)
-            return array[i];
-        return RT.eos();
-    }
-
-    static IStream createFromObject(Object array) {
-        Class aclass = array.getClass().getComponentType();
-        if (!aclass.isPrimitive())
-            return new ArrayStream((Object[]) array);
-        if (aclass == int.class)
-            return new ArrayStream_int((int[]) array);
-        if (aclass == long.class)
-            return new ArrayStream_long((long[]) array);
-        if (aclass == float.class)
-            return new ArrayStream_float((float[]) array);
-        if (aclass == double.class)
-            return new ArrayStream_double((double[]) array);
-        if (aclass == char.class)
-            return new ArrayStream_char((char[]) array);
-        if (aclass == byte.class)
-            return new ArrayStream_byte((byte[]) array);
-        if (aclass == short.class)
-            return new ArrayStream_short((short[]) array);
-        if (aclass == boolean.class)
-            return new ArrayStream_boolean((boolean[]) array);
-        throw new IllegalArgumentException(String.format("Unsupported array type %s", array));
-    }
-
-    static public class ArrayStream_int implements IStream {
-
-        final AtomicInteger ai = new AtomicInteger(0);
-        final int[] array;
-
-        public ArrayStream_int(int[] array) {
-            this.array = array;
-        }
-
-        public Object next() throws Exception {
-            int i = ai.getAndIncrement();
-            if (i < array.length)
-                return array[i];
-            return RT.eos();
-        }
-    }
-
-    static public class ArrayStream_long implements IStream {
-
-        final AtomicInteger ai = new AtomicInteger(0);
-        final long[] array;
-
-        public ArrayStream_long(long[] array) {
-            this.array = array;
-        }
-
-        public Object next() throws Exception {
-            int i = ai.getAndIncrement();
-            if (i < array.length)
-                return array[i];
-            return RT.eos();
-        }
-    }
-
-    static public class ArrayStream_float implements IStream {
-
-        final AtomicInteger ai = new AtomicInteger(0);
-        final float[] array;
-
-        public ArrayStream_float(float[] array) {
-            this.array = array;
-        }
-
-        public Object next() throws Exception {
-            int i = ai.getAndIncrement();
-            if (i < array.length)
-                return array[i];
-            return RT.eos();
-        }
-    }
-
-    static public class ArrayStream_double implements IStream {
-
-        final AtomicInteger ai = new AtomicInteger(0);
-        final double[] array;
-
-        public ArrayStream_double(double[] array) {
-            this.array = array;
-        }
-
-        public Object next() throws Exception {
-            int i = ai.getAndIncrement();
-            if (i < array.length)
-                return array[i];
-            return RT.eos();
-        }
-    }
-
-    static public class ArrayStream_char implements IStream {
-
-        final AtomicInteger ai = new AtomicInteger(0);
-        final char[] array;
-
-        public ArrayStream_char(char[] array) {
-            this.array = array;
-        }
-
-        public Object next() throws Exception {
-            int i = ai.getAndIncrement();
-            if (i < array.length)
-                return array[i];
-            return RT.eos();
-        }
-    }
-
-    static public class ArrayStream_byte implements IStream {
-
-        final AtomicInteger ai = new AtomicInteger(0);
-        final byte[] array;
-
-        public ArrayStream_byte(byte[] array) {
-            this.array = array;
-        }
-
-        public Object next() throws Exception {
-            int i = ai.getAndIncrement();
-            if (i < array.length)
-                return array[i];
-            return RT.eos();
-        }
-    }
-
-    static public class ArrayStream_short implements IStream {
-
-        final AtomicInteger ai = new AtomicInteger(0);
-        final short[] array;
-
-        public ArrayStream_short(short[] array) {
-            this.array = array;
-        }
-
-        public Object next() throws Exception {
-            int i = ai.getAndIncrement();
-            if (i < array.length)
-                return array[i];
-            return RT.eos();
-        }
-    }
-
-    static public class ArrayStream_boolean implements IStream {
-
-        final AtomicInteger ai = new AtomicInteger(0);
-        final boolean[] array;
-
-        public ArrayStream_boolean(boolean[] array) {
-            this.array = array;
-        }
-
-        public Object next() throws Exception {
-            int i = ai.getAndIncrement();
-            if (i < array.length)
-                return array[i];
-            return RT.eos();
-        }
-    }
+int i = 0;
+final Object[] array;
+
+public ArrayStream(Object[] array){
+	this.array = array;
+}
+
+public Object invoke() throws Exception{
+	if(i < array.length)
+		return array[i++];
+	return RT.EOS;
+}
+
+static Stream createFromObject(Object array){
+	Class aclass = array.getClass().getComponentType();
+	if(!aclass.isPrimitive())
+		return new Stream(new ArrayStream((Object[]) array));
+	if(aclass == int.class)
+		return new Stream(new ArrayStream_int((int[]) array));
+	if(aclass == long.class)
+		return new Stream(new ArrayStream_long((long[]) array));
+	if(aclass == float.class)
+		return new Stream(new ArrayStream_float((float[]) array));
+	if(aclass == double.class)
+		return new Stream(new ArrayStream_double((double[]) array));
+	if(aclass == char.class)
+		return new Stream(new ArrayStream_char((char[]) array));
+	if(aclass == byte.class)
+		return new Stream(new ArrayStream_byte((byte[]) array));
+	if(aclass == short.class)
+		return new Stream(new ArrayStream_short((short[]) array));
+	if(aclass == boolean.class)
+		return new Stream(new ArrayStream_boolean((boolean[]) array));
+	throw new IllegalArgumentException(String.format("Unsupported array type %s", array));
+}
+
+static public class ArrayStream_int extends AFn{
+
+	int i = 0;
+	final int[] array;
+
+	public ArrayStream_int(int[] array){
+		this.array = array;
+	}
+
+	public Object invoke() throws Exception{
+		if(i < array.length)
+			return array[i++];
+		return RT.EOS;
+	}
+}
+
+static public class ArrayStream_long extends AFn{
+
+	int i = 0;
+	final long[] array;
+
+	public ArrayStream_long(long[] array){
+		this.array = array;
+	}
+
+	public Object invoke() throws Exception{
+		if(i < array.length)
+			return array[i++];
+		return RT.EOS;
+	}
+}
+
+static public class ArrayStream_float extends AFn{
+
+	int i = 0;
+	final float[] array;
+
+	public ArrayStream_float(float[] array){
+		this.array = array;
+	}
+
+	public Object invoke() throws Exception{
+		if(i < array.length)
+			return array[i++];
+		return RT.EOS;
+	}
+}
+
+static public class ArrayStream_double extends AFn{
+
+	int i = 0;
+	final double[] array;
+
+	public ArrayStream_double(double[] array){
+		this.array = array;
+	}
+
+	public Object invoke() throws Exception{
+		if(i < array.length)
+			return array[i++];
+		return RT.EOS;
+	}
+}
+
+static public class ArrayStream_char extends AFn{
+
+	int i = 0;
+	final char[] array;
+
+	public ArrayStream_char(char[] array){
+		this.array = array;
+	}
+
+	public Object invoke() throws Exception{
+		if(i < array.length)
+			return array[i++];
+		return RT.EOS;
+	}
+}
+
+static public class ArrayStream_byte extends AFn{
+
+	int i = 0;
+	final byte[] array;
+
+	public ArrayStream_byte(byte[] array){
+		this.array = array;
+	}
+
+	public Object invoke() throws Exception{
+		if(i < array.length)
+			return array[i++];
+		return RT.EOS;
+	}
+}
+
+static public class ArrayStream_short extends AFn{
+
+	int i = 0;
+	final short[] array;
+
+	public ArrayStream_short(short[] array){
+		this.array = array;
+	}
+
+	public Object invoke() throws Exception{
+		if(i < array.length)
+			return array[i++];
+		return RT.EOS;
+	}
+}
+
+static public class ArrayStream_boolean extends AFn{
+
+	int i = 0;
+	final boolean[] array;
+
+	public ArrayStream_boolean(boolean[] array){
+		this.array = array;
+	}
+
+	public Object invoke() throws Exception{
+		if(i < array.length)
+			return array[i++];
+		return RT.EOS;
+	}
+}
 
 
 }
diff --git a/src/jvm/clojure/lang/IStream.java b/src/jvm/clojure/lang/IStream.java
deleted file mode 100644
index ccd8a9d8..00000000
--- a/src/jvm/clojure/lang/IStream.java
+++ /dev/null
@@ -1,17 +0,0 @@
-/**
- *   Copyright (c) Rich Hickey. All rights reserved.
- *   The use and distribution terms for this software are covered by the
- *   Eclipse Public License 1.0 (http://opensource.org/licenses/eclipse-1.0.php)
- *   which can be found in the file epl-v10.html at the root of this distribution.
- *   By using this software in any fashion, you are agreeing to be bound by
- * 	 the terms of this license.
- *   You must not remove this notice, or any other, from this software.
- **/
-
-/* rich Dec 7, 2008 */
-
-package clojure.lang;
-
-public interface IStream {
-    Object next() throws Exception;
-}
diff --git a/src/jvm/clojure/lang/IteratorStream.java b/src/jvm/clojure/lang/IteratorStream.java
index edb4dd79..484169b2 100644
--- a/src/jvm/clojure/lang/IteratorStream.java
+++ b/src/jvm/clojure/lang/IteratorStream.java
@@ -14,16 +14,16 @@ package clojure.lang;
 
 import java.util.Iterator;
 
-public class IteratorStream implements IStream{
-    final Iterator iter;
+public class IteratorStream extends AFn{
+final Iterator iter;
 
-    public IteratorStream(Iterator iter) {
-        this.iter = iter;
-    }
+IteratorStream(Iterator iter){
+	this.iter = iter;
+}
 
-    synchronized public Object next() throws Exception {
-        if(iter.hasNext())
-            return iter.next();
-        return RT.eos();
-    }
+public Object invoke() throws Exception{
+	if(iter.hasNext())
+		return iter.next();
+	return RT.EOS;
+}
 }
diff --git a/src/jvm/clojure/lang/RT.java b/src/jvm/clojure/lang/RT.java
index 5195cf82..31579965 100644
--- a/src/jvm/clojure/lang/RT.java
+++ b/src/jvm/clojure/lang/RT.java
@@ -220,11 +220,10 @@ final static IFn inNamespace = new AFn(){
 public static List<String> processCommandLine(String[] args){
 	List<String> arglist = Arrays.asList(args);
 	int split = arglist.indexOf("--");
-	if(split >= 0)
-		{
+	if(split >= 0) {
 		CMD_LINE_ARGS.bindRoot(RT.seq(arglist.subList(split + 1, args.length)));
 		return arglist.subList(0, split);
-		}
+	}
 	return arglist;
 }
 
@@ -243,8 +242,15 @@ static public void addURL(Object url) throws Exception{
 	getRootClassLoader().addURL(u);
 }
 
-static
-	{
+final static public Object EOS = new Object();
+final static public Object SKIP = new Object();
+static final public IFn EMPTY_GEN = new AFn(){
+    synchronized public Object invoke() throws Exception {
+        return EOS;
+    }
+};
+
+static{
 	Keyword dockw = Keyword.intern(null, "doc");
 	Keyword arglistskw = Keyword.intern(null, "arglists");
 	Symbol namesym = Symbol.create("name");
@@ -277,15 +283,13 @@ static
 	               });
 	v.setMeta(map(dockw, "Tests if 2 arguments are the same object",
 	              arglistskw, list(vector(Symbol.create("x"), Symbol.create("y")))));
-	try
-		{
+	try {
 		doInit();
-		}
-	catch(Exception e)
-		{
+	}
+	catch(Exception e) {
 		throw new RuntimeException(e);
-		}
 	}
+}
 
 
 static public Var var(String ns, String name){
@@ -316,21 +320,17 @@ public static void loadResourceScript(Class c, String name, boolean failIfNotFou
 	int slash = name.lastIndexOf('/');
 	String file = slash >= 0 ? name.substring(slash + 1) : name;
 	InputStream ins = baseLoader().getResourceAsStream(name);
-	if(ins != null)
-		{
-		try
-			{
+	if(ins != null) {
+		try {
 			Compiler.load(new InputStreamReader(ins, UTF8), name, file);
-			}
-		finally
-			{
+		}
+		finally {
 			ins.close();
-			}
 		}
-	else if(failIfNotFound)
-		{
+	}
+	else if(failIfNotFound) {
 		throw new FileNotFoundException("Could not locate Clojure resource on classpath: " + name);
-		}
+	}
 }
 
 static public void init() throws Exception{
@@ -338,31 +338,26 @@ static public void init() throws Exception{
 }
 
 static public long lastModified(URL url, String libfile) throws Exception{
-	if(url.getProtocol().equals("jar"))
-		{
+	if(url.getProtocol().equals("jar")) {
 		return ((JarURLConnection) url.openConnection()).getJarFile().getEntry(libfile).getTime();
-		}
-	else
-		{
+	}
+	else {
 		return url.openConnection().getLastModified();
-		}
+	}
 }
 
 static void compile(String cljfile) throws Exception{
 	InputStream ins = baseLoader().getResourceAsStream(cljfile);
-	if(ins != null)
-		{
-		try
-			{
+	if(ins != null) {
+		try {
 			Compiler.compile(new InputStreamReader(ins, UTF8), cljfile,
 			                 cljfile.substring(1 + cljfile.lastIndexOf("/")));
-			}
-		finally
-			{
+		}
+		finally {
 			ins.close();
-			}
-
 		}
+
+	}
 	else
 		throw new FileNotFoundException("Could not locate Clojure resource on classpath: " + cljfile);
 }
@@ -381,27 +376,23 @@ static public void load(String scriptbase, boolean failIfNotFound) throws Except
 	if((classURL != null &&
 	    (cljURL == null
 	     || lastModified(classURL, classfile) > lastModified(cljURL, cljfile)))
-	   || classURL == null)
-		{
-		try
-			{
+	   || classURL == null) {
+		try {
 			Var.pushThreadBindings(
 					RT.map(CURRENT_NS, CURRENT_NS.deref(),
 					       WARN_ON_REFLECTION, WARN_ON_REFLECTION.deref()));
 			loaded = (loadClassForName(scriptbase.replace('/', '.') + LOADER_SUFFIX) != null);
-			}
-		finally
-			{
+		}
+		finally {
 			Var.popThreadBindings();
-			}
 		}
-	if(!loaded && cljURL != null)
-		{
+	}
+	if(!loaded && cljURL != null) {
 		if(booleanCast(Compiler.COMPILE_FILES.deref()))
 			compile(cljfile);
 		else
 			loadResourceScript(RT.class, cljfile);
-		}
+	}
 	else if(!loaded && failIfNotFound)
 		throw new FileNotFoundException(String.format("Could not locate %s or %s on classpath: ", classfile, cljfile));
 }
@@ -415,8 +406,7 @@ static void doInit() throws Exception{
 	Var.pushThreadBindings(
 			RT.map(CURRENT_NS, CURRENT_NS.deref(),
 			       WARN_ON_REFLECTION, WARN_ON_REFLECTION.deref()));
-	try
-		{
+	try {
 		Symbol USER = Symbol.create("user");
 		Symbol CLOJURE = Symbol.create("clojure.core");
 
@@ -425,11 +415,10 @@ static void doInit() throws Exception{
 		in_ns.invoke(USER);
 		refer.invoke(CLOJURE);
 		maybeLoadResourceScript("user.clj");
-		}
-	finally
-		{
+	}
+	finally {
 		Var.popThreadBindings();
-		}
+	}
 }
 
 static public int nextID(){
@@ -448,29 +437,22 @@ static public ISeq seq(Object coll){
 		return seqFrom(coll);
 }
 
-static public IStream stream(final Object coll) throws Exception{
+static public Stream stream(final Object coll) throws Exception{
 	if(coll == null)
-		return EMPTY_STREAM;
-	else if(coll instanceof IStream)
-		return (IStream) coll;
+		return new Stream(EMPTY_GEN);
 	else if(coll instanceof Streamable)
-			return ((Streamable) coll).stream();
-		else if(coll instanceof Fn)
-				{
-				return new IStream(){
-					public Object next() throws Exception{
-						return ((IFn) coll).invoke();
-					}
-				};
-				}
-			else if(coll instanceof Iterable)
-					return new IteratorStream(((Iterable) coll).iterator());
-				else if(coll.getClass().isArray())
-						return ArrayStream.createFromObject(coll);
-					else if(coll instanceof String)
-							return ArrayStream.createFromObject(((String) coll).toCharArray());
+		return ((Streamable) coll).stream();
+	else if(coll instanceof Fn)
+		return new Stream((IFn) coll);
+	else if(coll instanceof Iterable)
+		return new Stream(new IteratorStream(((Iterable) coll).iterator()));
+	else if(coll.getClass().isArray())
+		return ArrayStream.createFromObject(coll);
+	else if(coll instanceof String)
+		return ArrayStream.createFromObject(((String) coll).toCharArray());
+	else
+	    return new Stream(new ASeq.Src(RT.seq(coll)));
 
-	throw new IllegalArgumentException("Don't know how to create IStream from: " + coll.getClass().getSimpleName());
 }
 
 static ISeq seqFrom(Object coll){
@@ -479,19 +461,18 @@ static ISeq seqFrom(Object coll){
 	else if(coll == null)
 		return null;
 	else if(coll instanceof Iterable)
-			return IteratorSeq.create(((Iterable) coll).iterator());
-		else if(coll.getClass().isArray())
-				return ArraySeq.createFromObject(coll);
-			else if(coll instanceof String)
-					return StringSeq.create((String) coll);
-				else if(coll instanceof Map)
-						return seq(((Map) coll).entrySet());
-					else
-						{
-						Class c = coll.getClass();
-						Class sc = c.getSuperclass();
-						throw new IllegalArgumentException("Don't know how to create ISeq from: " + c.getSimpleName());
-						}
+		return IteratorSeq.create(((Iterable) coll).iterator());
+	else if(coll.getClass().isArray())
+		return ArraySeq.createFromObject(coll);
+	else if(coll instanceof String)
+		return StringSeq.create((String) coll);
+	else if(coll instanceof Map)
+		return seq(((Map) coll).entrySet());
+	else {
+		Class c = coll.getClass();
+		Class sc = c.getSuperclass();
+		throw new IllegalArgumentException("Don't know how to create ISeq from: " + c.getSimpleName());
+	}
 }
 
 static public ISeq keys(Object coll){
@@ -513,27 +494,25 @@ public static int count(Object o){
 		return 0;
 	else if(o instanceof Counted)
 		return ((Counted) o).count();
-	else if(o instanceof IPersistentCollection)
-			{
-			ISeq s = seq(o);
-			o = null;
-			int i = 0;
-			for(; s != null; s = s.next())
-				{
-				if(s instanceof Counted)
-					return i + s.count();
-				i++;
-				}
-			return i;
-			}
-		else if(o instanceof String)
-				return ((String) o).length();
-			else if(o instanceof Collection)
-					return ((Collection) o).size();
-				else if(o instanceof Map)
-						return ((Map) o).size();
-					else if(o.getClass().isArray())
-							return Array.getLength(o);
+	else if(o instanceof IPersistentCollection) {
+		ISeq s = seq(o);
+		o = null;
+		int i = 0;
+		for(; s != null; s = s.next()) {
+			if(s instanceof Counted)
+				return i + s.count();
+			i++;
+		}
+		return i;
+	}
+	else if(o instanceof String)
+		return ((String) o).length();
+	else if(o instanceof Collection)
+		return ((Collection) o).size();
+	else if(o instanceof Map)
+		return ((Map) o).size();
+	else if(o.getClass().isArray())
+		return Array.getLength(o);
 
 	throw new UnsupportedOperationException("count not supported on this type: " + o.getClass().getSimpleName());
 }
@@ -627,23 +606,20 @@ static public Object get(Object coll, Object key){
 		return null;
 	else if(coll instanceof Associative)
 		return ((Associative) coll).valAt(key);
-	else if(coll instanceof Map)
-			{
-			Map m = (Map) coll;
-			return m.get(key);
-			}
-		else if(coll instanceof IPersistentSet)
-				{
-				IPersistentSet set = (IPersistentSet) coll;
-				return set.get(key);
-				}
-			else if(key instanceof Number && (coll instanceof String || coll.getClass().isArray()))
-					{
-					int n = ((Number) key).intValue();
-					if(n >= 0 && n < count(coll))
-						return nth(coll, n);
-					return null;
-					}
+	else if(coll instanceof Map) {
+		Map m = (Map) coll;
+		return m.get(key);
+	}
+	else if(coll instanceof IPersistentSet) {
+		IPersistentSet set = (IPersistentSet) coll;
+		return set.get(key);
+	}
+	else if(key instanceof Number && (coll instanceof String || coll.getClass().isArray())) {
+		int n = ((Number) key).intValue();
+		if(n >= 0 && n < count(coll))
+			return nth(coll, n);
+		return null;
+	}
 
 	return null;
 }
@@ -653,25 +629,22 @@ static public Object get(Object coll, Object key, Object notFound){
 		return notFound;
 	else if(coll instanceof Associative)
 		return ((Associative) coll).valAt(key, notFound);
-	else if(coll instanceof Map)
-			{
-			Map m = (Map) coll;
-			if(m.containsKey(key))
-				return m.get(key);
-			return notFound;
-			}
-		else if(coll instanceof IPersistentSet)
-				{
-				IPersistentSet set = (IPersistentSet) coll;
-				if(set.contains(key))
-					return set.get(key);
-				return notFound;
-				}
-			else if(key instanceof Number && (coll instanceof String || coll.getClass().isArray()))
-					{
-					int n = ((Number) key).intValue();
-					return n >= 0 && n < count(coll) ? nth(coll, n) : notFound;
-					}
+	else if(coll instanceof Map) {
+		Map m = (Map) coll;
+		if(m.containsKey(key))
+			return m.get(key);
+		return notFound;
+	}
+	else if(coll instanceof IPersistentSet) {
+		IPersistentSet set = (IPersistentSet) coll;
+		if(set.contains(key))
+			return set.get(key);
+		return notFound;
+	}
+	else if(key instanceof Number && (coll instanceof String || coll.getClass().isArray())) {
+		int n = ((Number) key).intValue();
+		return n >= 0 && n < count(coll) ? nth(coll, n) : notFound;
+	}
 	return notFound;
 
 }
@@ -688,17 +661,15 @@ static public Object contains(Object coll, Object key){
 	else if(coll instanceof Associative)
 		return ((Associative) coll).containsKey(key) ? T : F;
 	else if(coll instanceof IPersistentSet)
-			return ((IPersistentSet) coll).contains(key) ? T : F;
-		else if(coll instanceof Map)
-				{
-				Map m = (Map) coll;
-				return m.containsKey(key) ? T : F;
-				}
-			else if(key instanceof Number && (coll instanceof String || coll.getClass().isArray()))
-					{
-					int n = ((Number) key).intValue();
-					return n >= 0 && n < count(coll);
-					}
+		return ((IPersistentSet) coll).contains(key) ? T : F;
+	else if(coll instanceof Map) {
+		Map m = (Map) coll;
+		return m.containsKey(key) ? T : F;
+	}
+	else if(key instanceof Number && (coll instanceof String || coll.getClass().isArray())) {
+		int n = ((Number) key).intValue();
+		return n >= 0 && n < count(coll);
+	}
 	return F;
 }
 
@@ -707,28 +678,26 @@ static public Object find(Object coll, Object key){
 		return null;
 	else if(coll instanceof Associative)
 		return ((Associative) coll).entryAt(key);
-	else
-		{
+	else {
 		Map m = (Map) coll;
 		if(m.containsKey(key))
 			return new MapEntry(key, m.get(key));
 		return null;
-		}
+	}
 }
 
 //takes a seq of key,val,key,val
 
 //returns tail starting at val of matching key if found, else null
 static public ISeq findKey(Keyword key, ISeq keyvals) throws Exception{
-	while(keyvals != null)
-		{
+	while(keyvals != null) {
 		ISeq r = keyvals.next();
 		if(r == null)
 			throw new Exception("Malformed keyword argslist");
 		if(keyvals.first() == key)
 			return r;
 		keyvals = r.next();
-		}
+	}
 	return null;
 }
 
@@ -744,38 +713,35 @@ static public Object nth(Object coll, int n){
 	else if(coll instanceof IPersistentVector)
 		return ((IPersistentVector) coll).nth(n);
 	else if(coll instanceof String)
-			return Character.valueOf(((String) coll).charAt(n));
-		else if(coll.getClass().isArray())
-				return Reflector.prepRet(Array.get(coll, n));
-			else if(coll instanceof RandomAccess)
-					return ((List) coll).get(n);
-				else if(coll instanceof Matcher)
-						return ((Matcher) coll).group(n);
-
-					else if(coll instanceof Map.Entry)
-							{
-							Map.Entry e = (Map.Entry) coll;
-							if(n == 0)
-								return e.getKey();
-							else if(n == 1)
-								return e.getValue();
-							throw new IndexOutOfBoundsException();
-							}
-
-						else if(coll instanceof Sequential)
-								{
-								ISeq seq = RT.seq(coll);
-								coll = null;
-								for(int i = 0; i <= n && seq != null; ++i, seq = seq.next())
-									{
-									if(i == n)
-										return seq.first();
-									}
-								throw new IndexOutOfBoundsException();
-								}
-							else
-								throw new UnsupportedOperationException(
-										"nth not supported on this type: " + coll.getClass().getSimpleName());
+		return Character.valueOf(((String) coll).charAt(n));
+	else if(coll.getClass().isArray())
+		return Reflector.prepRet(Array.get(coll, n));
+	else if(coll instanceof RandomAccess)
+		return ((List) coll).get(n);
+	else if(coll instanceof Matcher)
+		return ((Matcher) coll).group(n);
+
+	else if(coll instanceof Map.Entry) {
+		Map.Entry e = (Map.Entry) coll;
+		if(n == 0)
+			return e.getKey();
+		else if(n == 1)
+			return e.getValue();
+		throw new IndexOutOfBoundsException();
+	}
+
+	else if(coll instanceof Sequential) {
+		ISeq seq = RT.seq(coll);
+		coll = null;
+		for(int i = 0; i <= n && seq != null; ++i, seq = seq.next()) {
+			if(i == n)
+				return seq.first();
+		}
+		throw new IndexOutOfBoundsException();
+	}
+	else
+		throw new UnsupportedOperationException(
+				"nth not supported on this type: " + coll.getClass().getSimpleName());
 }
 
 static public Object nth(Object coll, int n, Object notFound){
@@ -783,63 +749,55 @@ static public Object nth(Object coll, int n, Object notFound){
 		return notFound;
 	else if(n < 0)
 		return notFound;
-	else if(coll instanceof IPersistentVector)
-			{
-			IPersistentVector v = (IPersistentVector) coll;
-			if(n < v.count())
-				return v.nth(n);
-			return notFound;
-			}
-		else if(coll instanceof String)
-				{
-				String s = (String) coll;
-				if(n < s.length())
-					return Character.valueOf(s.charAt(n));
-				return notFound;
-				}
-			else if(coll.getClass().isArray())
-					{
-					if(n < Array.getLength(coll))
-						return Reflector.prepRet(Array.get(coll, n));
-					return notFound;
-					}
-				else if(coll instanceof RandomAccess)
-						{
-						List list = (List) coll;
-						if(n < list.size())
-							return list.get(n);
-						return notFound;
-						}
-					else if(coll instanceof Matcher)
-							{
-							Matcher m = (Matcher) coll;
-							if(n < m.groupCount())
-								return m.group(n);
-							return notFound;
-							}
-						else if(coll instanceof Map.Entry)
-								{
-								Map.Entry e = (Map.Entry) coll;
-								if(n == 0)
-									return e.getKey();
-								else if(n == 1)
-									return e.getValue();
-								return notFound;
-								}
-							else if(coll instanceof Sequential)
-									{
-									ISeq seq = RT.seq(coll);
-									coll = null;
-									for(int i = 0; i <= n && seq != null; ++i, seq = seq.next())
-										{
-										if(i == n)
-											return seq.first();
-										}
-									return notFound;
-									}
-								else
-									throw new UnsupportedOperationException(
-											"nth not supported on this type: " + coll.getClass().getSimpleName());
+	else if(coll instanceof IPersistentVector) {
+		IPersistentVector v = (IPersistentVector) coll;
+		if(n < v.count())
+			return v.nth(n);
+		return notFound;
+	}
+	else if(coll instanceof String) {
+		String s = (String) coll;
+		if(n < s.length())
+			return Character.valueOf(s.charAt(n));
+		return notFound;
+	}
+	else if(coll.getClass().isArray()) {
+		if(n < Array.getLength(coll))
+			return Reflector.prepRet(Array.get(coll, n));
+		return notFound;
+	}
+	else if(coll instanceof RandomAccess) {
+		List list = (List) coll;
+		if(n < list.size())
+			return list.get(n);
+		return notFound;
+	}
+	else if(coll instanceof Matcher) {
+		Matcher m = (Matcher) coll;
+		if(n < m.groupCount())
+			return m.group(n);
+		return notFound;
+	}
+	else if(coll instanceof Map.Entry) {
+		Map.Entry e = (Map.Entry) coll;
+		if(n == 0)
+			return e.getKey();
+		else if(n == 1)
+			return e.getValue();
+		return notFound;
+	}
+	else if(coll instanceof Sequential) {
+		I