--- a/core/src/luan/modules/BinaryLuan.java	Thu Dec 18 12:06:56 2014 +0000
+++ b/core/src/luan/modules/BinaryLuan.java	Fri Dec 19 07:50:46 2014 +0000
@@ -10,16 +10,56 @@
 
 public final class BinaryLuan {
 
-	@LuanMethod public static byte[] pack(byte... bytes) {
-		return bytes;
+	public static Object __index(LuanState luan,final byte[] binary,Object key) throws LuanException {
+		LuanTable mod = (LuanTable)PackageLuan.loaded(luan).get("luan:Binary");
+		if( mod!=null ) {
+			Object obj = mod.get(key);
+			if( obj instanceof LuanFunction ) {
+				final LuanFunction fn = (LuanFunction)obj;
+				return new LuanFunction() {
+					@Override public Object call(LuanState luan,Object[] args) throws LuanException {
+						Object[] a = new Object[args.length+1];
+						a[0] = binary;
+						System.arraycopy(args,0,a,1,args.length);
+						return fn.call(luan,a);
+					}
+				};
+			}
+		}
+		return null;
 	}
 
-	@LuanMethod public static Byte[] unpack(byte[] binary) {
-		Byte[] bytes = new Byte[binary.length];
-		for( int i=0; i<binary.length; i++ ) {
-			bytes[i] = binary[i];
+	static int start(byte[] binary,int i) {
+		int len = binary.length;
+		return i==0 ? 0 : i > 0 ? Math.min(i-1,len) : Math.max(len+i,0);
+	}
+
+	static int start(byte[] binary,Integer i,int dflt) {
+		return i==null ? dflt : start(binary,i);
+	}
+
+	static int end(byte[] binary,int i) {
+		int len = binary.length;
+		return i==0 ? 0 : i > 0 ? Math.min(i,len) : Math.max(len+i+1,0);
+	}
+
+	static int end(byte[] binary,Integer i,int dflt) {
+		return i==null ? dflt : end(binary,i);
+	}
+
+	@LuanMethod public static Byte[] byte_(LuanState luan,byte[] binary,Integer i,Integer j) throws LuanException {
+		Utils.checkNotNull(luan,binary);
+		int start = start(binary,i,1);
+		int end = end(binary,j,start+1);
+		Byte[] bytes = new Byte[end-start];
+		for( int k=0; k<bytes.length; k++ ) {
+			bytes[k] = binary[start+k];
 		}
 		return bytes;
 	}
 
+	@LuanMethod public static byte[] binary(byte... bytes) {
+		return bytes;
+	}
+
 }