fix bug: invoke overload method disorder

fix invoke java overload method disorder problem
Fix #66 : Broken license link.
2022-06-09 20:37:41 +08:00 · 2020-04-01 19:36:00 +03:00 · 2020-04-01 19:31:39 +03:00 · 2019-12-29 16:46:58 +02:00 · 2019-12-16 15:31:13 +02:00 · 2019-12-15 20:39:26 +02:00
47 changed files with 2971 additions and 2604 deletions
--- a/.gitignore
+++ b/.gitignore
@@ -1,8 +1,8 @@
-bin
+bin/
-target
+target/
-build
+build/
-lib
+lib/
-jit
+jit/
 *.ser
 *.gz
 *.jar
--- a/21
+++ b/21
@@ -0,0 +1,21 @@
 MIT License
 Copyright (c) 2007 LuaJ. All rights reserved.
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
 in the Software without restriction, including without limitation the rights
 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 copies of the Software, and to permit persons to whom the Software is
 furnished to do so, subject to the following conditions:
 The above copyright notice and this permission notice shall be included in all
 copies or substantial portions of the Software.
 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 SOFTWARE.
--- a/README.html
+++ b/README.html
@@ -1,27 +1,24 @@
-<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
+# This is a fork!
-<html>
+<div style="border: 1px dotted red; margin: 1.em 0.5em; font-weight: bold; color: red;">
 This repository has been forked from the original CVS sources of Luaj.
 The commit history has been converted to make sure that the original work of
 James Roseborough and Ian Farmer is not lost.
 Unfortunately, I was not able to contact either James or Ian to hand over
 ownership of the Github organization/repo as I have originally intended to.
 The community however seems interested enough to continue work on the original
 sources and therefore I have decided to make sure that any useful pull requests
 that may add some value to the original code base shall be merged in from now
 on.<br>
 -- Benjamin P. Jung, Jan. 26th 2018
 </div>
-<head>
+<h1>Getting Started with LuaJ</h1>
-<title>Getting Started with LuaJ</title>
+James Roseborough, Ian Farmer, Version 3.0.2
 <link rel="stylesheet" type="text/css" href="http://www.lua.org/lua.css">
 <META HTTP-EQUIV="content-type" CONTENT="text/html; charset=iso-8859-1">
 </head>
 <body>
 <hr>
 <h1>
 <a href="README.html"><img src="http://sourceforge.net/dbimage.php?id=196139" alt="" border="0"></a>
 Getting Started with LuaJ
 </h1>
 James Roseborough, Ian Farmer, Version 3.0.1
 <p>
 <small>
 Copyright &copy; 2009-2014 Luaj.org.
 Freely available under the terms of the
-<a href="http://sourceforge.net/dbimage.php?id=196142">Luaj license</a>.
+<a href="LICENSE">Luaj license</a>.
 </small>
 <hr>
 <p>
@@ -120,7 +117,7 @@ in comparison with the standard C distribution.
 	<td>16.794</td>
 	<td>11.274</td>
 	<td>Java</td>
-	<td>java -cp luaj-jse-3.0.1.jar;bcel-5.2.jar lua <b>-b</b> fannkuch.lua 10</td></tr>
+	<td>java -cp luaj-jse-3.0.2.jar;bcel-5.2.jar lua <b>-b</b> fannkuch.lua 10</td></tr>
 <tr valign="top">
 	<td></td>
 	<td></td>
@@ -130,7 +127,7 @@ in comparison with the standard C distribution.
 	<td>36.894</td>
 	<td>15.163</td>
 	<td></td>
-	<td>java -cp luaj-jse-3.0.1.jar lua -n fannkuch.lua 10</td></tr>
+	<td>java -cp luaj-jse-3.0.2.jar lua -n fannkuch.lua 10</td></tr>
 <tr valign="top">
 	<td>lua</td>
 	<td>5.1.4</td>
@@ -186,7 +183,7 @@ It is also faster than Java-lua implementations Jill, Kahlua, and Mochalua for a
 From the main distribution directory line type:
 <pre>
-	java -cp lib/luaj-jse-3.0.1.jar lua examples/lua/hello.lua
+	java -cp luaj-jse-3.0.2.jar lua examples/lua/hello.lua
 </pre>
 <p>
@@ -198,7 +195,7 @@ You should see the following output:
 To see how luaj can be used to acccess most Java API's including swing, try:
 <pre>
-	java -cp lib/luaj-jse-3.0.1.jar lua examples/lua/swingapp.lua
+	java -cp luaj-jse-3.0.2.jar lua examples/lua/swingapp.lua
 </pre>
 <p>
@@ -213,8 +210,8 @@ Links to sources:<pre>
 From the main distribution directory line type:
 <pre>
-	java -cp lib/luaj-jse-3.0.1.jar luac examples/lua/hello.lua
+	java -cp luaj-jse-3.0.2.jar luac examples/lua/hello.lua
-	java -cp lib/luaj-jse-3.0.1.jar lua luac.out
+	java -cp luaj-jse-3.0.2.jar lua luac.out
 </pre>
 <p>
@@ -228,8 +225,8 @@ Luaj can compile lua sources or binaries directly to java bytecode if the bcel l
 <pre>
 	ant bcel-lib
-	java -cp &quot;lib/luaj-jse-3.0.1.jar;lib/bcel-5.2.jar&quot; luajc -s examples/lua -d . hello.lua
+	java -cp &quot;luaj-jse-3.0.2.jar;lib/bcel-5.2.jar&quot; luajc -s examples/lua -d . hello.lua
-	java -cp &quot;lib/luaj-jse-3.0.1.jar;.&quot; lua -l hello
+	java -cp &quot;luaj-jse-3.0.2.jar;.&quot; lua -l hello
 </pre>
 <p>
@@ -240,7 +237,7 @@ but the compiled classes must be in the class path at runtime, unless runtime ji
 <p>
 Lua scripts can also be run directly in this mode without precompiling using the <em>lua</em> command with the <b><em>-b</em></b> option and providing the <em>bcel</em> library in the class path:
 <pre>
-	java -cp &quot;lib/luaj-jse-3.0.1.jar;lib/bcel-5.2.jar&quot; lua -b examples/lua/hello.lua
+	java -cp &quot;luaj-jse-3.0.2.jar;lib/bcel-5.2.jar&quot; lua -b examples/lua/hello.lua
 </pre>
@@ -284,7 +281,7 @@ A simple example may be found in
 </pre>
 <p>
-You must include the library <b>lib/luaj-jse-3.0.1.jar</b> in your class path.
+You must include the library <b>luaj-jse-3.0.2.jar</b> in your class path.
 <h2>Run a script in a MIDlet</h2>
@@ -311,7 +308,7 @@ A simple example may be found in
 </pre>
 <p>
-You must include the library <b>lib/luaj-jme-3.0.1.jar</b> in your midlet jar.
+You must include the library <b>luaj-jme-3.0.2.jar</b> in your midlet jar.
 <p>
 An ant script to build and run the midlet is in
@@ -341,7 +338,7 @@ You can also look up the engine by language "lua" or mimetypes "text/lua" or "ap
 All standard aspects of script engines including compiled statements are supported.
 <p>
-You must include the library <b>lib/luaj-jse-3.0.1.jar</b> in your class path.
+You must include the library <b>luaj-jse-3.0.2.jar</b> in your class path.
 <p>
 A working example may be found in
@@ -352,8 +349,8 @@ A working example may be found in
 To compile and run it using Java 1.6 or higher:
 <pre>
-	javac -cp lib/luaj-jse-3.0.1.jar examples/jse/ScriptEngineSample.java
+	javac -cp luaj-jse-3.0.2.jar examples/jse/ScriptEngineSample.java
-	java -cp &quot;lib/luaj-jse-3.0.1.jar;examples/jse&quot; ScriptEngineSample
+	java -cp &quot;luaj-jse-3.0.2.jar;examples/jse&quot; ScriptEngineSample
 </pre>
 <h2>Excluding the lua bytecode compiler</h2>
@@ -415,7 +412,7 @@ and the math operations include all those supported by Java SE.
 Android applications should use the JsePlatform, and can include the <a href="#luajava">Luajava</a> library 
 to simplify access to underlying Android APIs.  
 A specialized Globals.finder should be provided to find scripts and data for loading.
-See <a href="examples/android/src/android/LuajView">examples/android/src/android/LuajView</a>
+See <a href="examples/android/src/android/LuajView.java">examples/android/src/android/LuajView.java</a>
 for an example that loads from the "res" Android project directory.
 The ant build script is <a href="examples/android/build.xml">examples/android/build.xml</a>.  
@@ -593,7 +590,7 @@ The following lua script will open a swing frame on Java SE:
 See a longer sample in <em>examples/lua/swingapp.lua</em> for details, including a simple animation loop, rendering graphics, mouse and key handling, and image loading. 
 Or try running it using: 
 <pre>
-	java -cp lib/luaj-jse-3.0.1.jar lua examples/lua/swingapp.lua
+	java -cp luaj-jse-3.0.2.jar lua examples/lua/swingapp.lua
 </pre>
 <p>
@@ -842,7 +839,7 @@ For JSE projects, add this dependency for the luaj-jse jar:
   &lt;dependency&gt;
      &lt;groupId&gt;org.luaj&lt;/groupId&gt;
      &lt;artifactId&gt;luaj-jse&lt;/artifactId&gt;
-      &lt;version&gt;3.0.1&lt;/version&gt;
+      &lt;version&gt;3.0.2&lt;/version&gt;
   &lt;/dependency&gt;	
 </pre>
 while for JME projects, use the luaj-jme jar:
@@ -850,7 +847,7 @@ while for JME projects, use the luaj-jme jar:
   &lt;dependency&gt;
      &lt;groupId&gt;org.luaj&lt;/groupId&gt;
      &lt;artifactId&gt;luaj-jme&lt;/artifactId&gt;
-      &lt;version&gt;3.0.1&lt;/version&gt;
+      &lt;version&gt;3.0.2&lt;/version&gt;
   &lt;/dependency&gt;	
 </pre>
@@ -880,7 +877,7 @@ Unit test scripts can be found in these locations
 	test/lua/*.lua
 	test/lua/errors/*.lua
 	test/lua/perf/*.lua
-	test/lua/luaj3.0.1-tests.zip
+	test/lua/luaj3.0.2-tests.zip
 </pre>
 <h2>Code coverage</h2>
@@ -930,7 +927,7 @@ Files are no longer hosted at LuaForge.
 <li>Enhance javadoc, put it <a href="docs/api/index.html">in distribution</a> 
 and at <a href="http://luaj.sourceforge.net/api/2.0/index.html">http://luaj.sourceforge.net/api/2.0/</a></li>
 <li>Major refactor of luajava type coercion logic, improve method selection.</li> 
-<li>Add lib/luaj-sources-2.0.2.jar for easier integration into an IDE such as Netbeans </li>
+<li>Add luaj-sources-2.0.2.jar for easier integration into an IDE such as Netbeans </li>
 <tr valign="top"><td>&nbsp;&nbsp;<b>2.0.3</b></td><td><ul>
 <li>Improve coroutine state logic including let unreferenced coroutines be garbage collected </li>
@@ -1017,6 +1014,11 @@ and at <a href="http://luaj.sourceforge.net/api/2.0/index.html">http://luaj.sour
 <li>Move online docs to <a href="http://luaj.org/luaj/3.0/api/index.html">http://luaj.org/luaj/3.0/api/</a></li>
 <li>Fix os.time() conversions for pm times.</li>
 <tr valign="top"><td>&nbsp;&nbsp;<b>3.0.2</b></td><td><ul>
 <li>Fix JsePlatform.luaMain() to provide an "arg" table in the chunk's environment.</li>
 <li>Let JsePlatform.luaMain() return values returned by the main chunk.</li>
 <li>Add synchronization to CoerceJavaToLua.COERCIONS map.</li>
 </ul></td></tr>
 </table></td></tr></table>
--- a/build.xml
+++ b/build.xml
@@ -82,17 +82,21 @@
 			<pathelement path="lib/mmapi.jar"/>
 		</path>
 		<javac destdir="build/jme/classes" encoding="utf-8" source="1.3" target="1.2" bootclasspathref="wtk-libs"
 		    debug="on"
 			srcdir="build/jme/src"/>
 		<javac destdir="build/jse/classes" encoding="utf-8" source="1.3" target="1.3"
 			classpath="lib/bcel-5.2.jar"
 			debug="on"
 			srcdir="build/jse/src"
 			excludes="**/script/*,**/Lua2Java*,**/server/*,lua*"/>
 		<javac destdir="build/jse/classes" encoding="utf-8" source="1.5" target="1.5"
 			classpath="build/jse/classes"
 			debug="on"
 			srcdir="build/jse/src"
 			includes="**/script/*,**/Lua2Java*,**/server/*"/>
 		<javac destdir="build/jse/classes" encoding="utf-8" source="1.3" target="1.3"
 			classpath="build/jse/classes"
 			debug="on"
 			srcdir="build/jse/src"
 			includes="lua*"/>
 	</target>
--- a/examples/jse/SampleApplet.java
+++ b/examples/jse/SampleApplet.java
@@ -11,13 +11,13 @@ import org.luaj.vm2.lib.Bit32Lib;
 import org.luaj.vm2.lib.CoroutineLib;
 import org.luaj.vm2.lib.PackageLib;
 import org.luaj.vm2.lib.ResourceFinder;
 import org.luaj.vm2.lib.StringLib;
 import org.luaj.vm2.lib.TableLib;
 import org.luaj.vm2.lib.jse.CoerceJavaToLua;
 import org.luaj.vm2.lib.jse.JseBaseLib;
 import org.luaj.vm2.lib.jse.JseIoLib;
 import org.luaj.vm2.lib.jse.JseMathLib;
 import org.luaj.vm2.lib.jse.JseOsLib;
 import org.luaj.vm2.lib.jse.JseStringLib;
 import org.luaj.vm2.lib.jse.LuajavaLib;
 /**
@@ -76,7 +76,7 @@ public class SampleApplet extends Applet implements ResourceFinder {
 		globals.load(new PackageLib());
 		globals.load(new Bit32Lib());
 		globals.load(new TableLib());
-		globals.load(new StringLib());
+		globals.load(new JseStringLib());
 		globals.load(new CoroutineLib());
 		globals.load(new JseMathLib());
 		globals.load(new JseIoLib());
--- a/examples/jse/SampleSandboxed.java
+++ b/examples/jse/SampleSandboxed.java
@@ -1,7 +1,21 @@
-import org.luaj.vm2.*;
+import org.luaj.vm2.Globals;
 import org.luaj.vm2.LoadState;
 import org.luaj.vm2.LuaBoolean;
 import org.luaj.vm2.LuaString;
 import org.luaj.vm2.LuaTable;
 import org.luaj.vm2.LuaThread;
 import org.luaj.vm2.LuaValue;
 import org.luaj.vm2.Varargs;
 import org.luaj.vm2.compiler.LuaC;
-import org.luaj.vm2.lib.*;
+import org.luaj.vm2.lib.Bit32Lib;
-import org.luaj.vm2.lib.jse.*;
+import org.luaj.vm2.lib.DebugLib;
 import org.luaj.vm2.lib.PackageLib;
 import org.luaj.vm2.lib.TableLib;
 import org.luaj.vm2.lib.TwoArgFunction;
 import org.luaj.vm2.lib.ZeroArgFunction;
 import org.luaj.vm2.lib.jse.JseBaseLib;
 import org.luaj.vm2.lib.jse.JseMathLib;
 import org.luaj.vm2.lib.jse.JseStringLib;
 /** Simple program that illustrates basic sand-boxing of client scripts
 * in a server environment.
@@ -29,7 +43,7 @@ public class SampleSandboxed {
 		server_globals = new Globals();
 		server_globals.load(new JseBaseLib());
 		server_globals.load(new PackageLib());
-		server_globals.load(new StringLib());
+		server_globals.load(new JseStringLib());
 		// To load scripts, we occasionally need a math library in addition to compiler support.
 		// To limit scripts using the debug library, they must be closures, so we only install LuaC.
@@ -82,7 +96,7 @@ public class SampleSandboxed {
 		user_globals.load(new PackageLib());
 		user_globals.load(new Bit32Lib());
 		user_globals.load(new TableLib());
-		user_globals.load(new StringLib());
+		user_globals.load(new JseStringLib());
 		user_globals.load(new JseMathLib());
 		// This library is dangerous as it gives unfettered access to the
--- a/src/core/org/luaj/vm2/LoadState.java
+++ b/src/core/org/luaj/vm2/LoadState.java
@@ -155,7 +155,6 @@ public class LoadState {
 	private static final LuaValue[]     NOVALUES    = {};
 	private static final Prototype[] NOPROTOS    = {};
 	private static final LocVars[]   NOLOCVARS   = {};
 	private static final LuaString[]  NOSTRVALUES = {};
 	private static final Upvaldesc[]  NOUPVALDESCS = {};
 	private static final int[]       NOINTS      = {};
--- a/src/core/org/luaj/vm2/Lua.java
+++ b/src/core/org/luaj/vm2/Lua.java
@@ -80,7 +80,6 @@ public class Lua {
 	public static final int POS_Bx		= POS_C;
 	public static final int POS_Ax		= POS_A;
 	public static final int MAX_OP          = ((1<<SIZE_OP)-1);
 	public static final int MAXARG_A        = ((1<<SIZE_A)-1);
 	public static final int MAXARG_B        = ((1<<SIZE_B)-1);
@@ -94,6 +93,7 @@ public class Lua {
 	public static final int MASK_B  = ((1<<SIZE_B)-1)<<POS_B;
 	public static final int MASK_C  = ((1<<SIZE_C)-1)<<POS_C;
 	public static final int MASK_Bx = ((1<<SIZE_Bx)-1)<<POS_Bx;
 	public static final int MASK_Ax = ((1<<SIZE_Ax)-1)<<POS_Ax;
 	public static final int MASK_NOT_OP = ~MASK_OP;
 	public static final int MASK_NOT_A  = ~MASK_A;
@@ -208,7 +208,7 @@ public class Lua {
 	public static final int OP_CONCAT = 22; /*	A B C	R(A) := R(B).. ... ..R(C)			*/
-	public static final int OP_JMP = 23; /*	sBx	pc+=sBx					*/
+	public static final int OP_JMP = 23; /*	A sBx	pc+=sBx; if (A) close all upvalues >= R(A - 1)	*/
 	public static final int OP_EQ = 24; /*	A B C	if ((RK(B) == RK(C)) ~= A) then pc++		*/
 	public static final int OP_LT = 25; /*	A B C	if ((RK(B) <  RK(C)) ~= A) then pc++  		*/
 	public static final int OP_LE = 26; /*	A B C	if ((RK(B) <= RK(C)) ~= A) then pc++  		*/
--- a/src/core/org/luaj/vm2/LuaClosure.java
+++ b/src/core/org/luaj/vm2/LuaClosure.java
@@ -21,6 +21,8 @@
 ******************************************************************************/
 package org.luaj.vm2;
 import org.luaj.vm2.lib.DebugLib.CallFrame;
 /**
 * Extension of {@link LuaFunction} which executes lua bytecode.
 * <p>
@@ -97,15 +99,20 @@ public class LuaClosure extends LuaFunction {
 	 */
 	public LuaClosure(Prototype p, LuaValue env) {
 		this.p = p;
 		this.initupvalue1(env);
 		globals = env instanceof Globals? (Globals) env: null;
 	}
 	public void initupvalue1(LuaValue env) {
 		if (p.upvalues == null || p.upvalues.length == 0)
 			this.upValues = NOUPVALUES;
 		else {
 			this.upValues = new UpValue[p.upvalues.length];
 			this.upValues[0] = new UpValue(new LuaValue[] {env}, 0);
 		}
 		globals = env instanceof Globals? (Globals) env: null;	
 	}
 	public boolean isclosure() {
 		return true;
 	}
@@ -118,26 +125,24 @@ public class LuaClosure extends LuaFunction {
 		return this;
 	}
 	public LuaValue getmetatable() { 
 		return s_metatable; 
 	}
 	public String tojstring() {
 		return "function: " + p.toString();
 	}
 	private LuaValue[] getNewStack() {
 		int max = p.maxstacksize;
 		LuaValue[] stack = new LuaValue[max];
 		System.arraycopy(NILS, 0, stack, 0, max);
 		return stack;
 	}
 	public final LuaValue call() {
-		LuaValue[] stack = new LuaValue[p.maxstacksize];
+		LuaValue[] stack = getNewStack();
 		for (int i = 0; i < p.numparams; ++i )
 			stack[i] = NIL;
 		return execute(stack,NONE).arg1();
 	}
 	public final LuaValue call(LuaValue arg) {
-		LuaValue[] stack = new LuaValue[p.maxstacksize];
+		LuaValue[] stack = getNewStack();
 		System.arraycopy(NILS, 0, stack, 0, p.maxstacksize);
 		for (int i = 1; i < p.numparams; ++i )
 			stack[i] = NIL;
 		switch ( p.numparams ) {
 		default: stack[0]=arg; return execute(stack,NONE).arg1();
 		case 0: return execute(stack,arg).arg1();
@@ -145,9 +150,7 @@ public class LuaClosure extends LuaFunction {
 	}
 	public final LuaValue call(LuaValue arg1, LuaValue arg2) {
-		LuaValue[] stack = new LuaValue[p.maxstacksize];
+		LuaValue[] stack = getNewStack();
 		for (int i = 2; i < p.numparams; ++i )
 			stack[i] = NIL;
 		switch ( p.numparams ) {
 		default: stack[0]=arg1; stack[1]=arg2; return execute(stack,NONE).arg1();
 		case 1: stack[0]=arg1; return execute(stack,arg2).arg1();
@@ -156,9 +159,7 @@ public class LuaClosure extends LuaFunction {
 	}
 	public final LuaValue call(LuaValue arg1, LuaValue arg2, LuaValue arg3) {
-		LuaValue[] stack = new LuaValue[p.maxstacksize];
+		LuaValue[] stack = getNewStack();
 		for (int i = 3; i < p.numparams; ++i )
 			stack[i] = NIL;
 		switch ( p.numparams ) {
 		default: stack[0]=arg1; stack[1]=arg2; stack[2]=arg3; return execute(stack,NONE).arg1();
 		case 2: stack[0]=arg1; stack[1]=arg2; return execute(stack,arg3).arg1();
@@ -172,7 +173,7 @@ public class LuaClosure extends LuaFunction {
 	}
 	public final Varargs onInvoke(Varargs varargs) {
-		LuaValue[] stack = new LuaValue[p.maxstacksize];
+		LuaValue[] stack = getNewStack();
 		for ( int i=0; i<p.numparams; i++ )
 			stack[i] = varargs.arg(i+1);
 		return execute(stack,p.is_vararg!=0? varargs.subargs(p.numparams+1): NONE);
@@ -215,6 +216,17 @@ public class LuaClosure extends LuaFunction {
 					stack[a] = k[i>>>14];
 					continue;
 				case Lua.OP_LOADKX:/*	A 	R(A) := Kst(extra arg)					*/
 					++pc;
 					i = code[pc];
 					if ((i & 0x3f) != Lua.OP_EXTRAARG) {
 						int op = i & 0x3f;
 						throw new LuaError("OP_EXTRAARG expected after OP_LOADKX, got " +
 							(op < Print.OPNAMES.length - 1 ? Print.OPNAMES[op] : "UNKNOWN_OP_" + op));
 					}
 					stack[a] = k[i>>>6];
 					continue;
 				case Lua.OP_LOADBOOL:/*	A B C	R(A):= (Bool)B: if (C) pc++			*/
 	                stack[a] = (i>>>23!=0)? LuaValue.TRUE: LuaValue.FALSE;
 	                if ((i&(0x1ff<<14)) != 0)
@@ -302,7 +314,7 @@ public class LuaClosure extends LuaFunction {
 						if ( c > b+1 ) {
 							Buffer sb = stack[c].buffer();
 							while ( --c>=b )
-								sb = stack[c].concat(sb);
+								sb.concatTo(stack[c]);
 							stack[a] = sb.value();
 						} else {
 							stack[a] = stack[c-1].concat(stack[c]);
@@ -310,7 +322,7 @@ public class LuaClosure extends LuaFunction {
 					}
 					continue;
-				case Lua.OP_JMP: /*	sBx	pc+=sBx					*/
+				case Lua.OP_JMP: /*	A sBx	pc+=sBx; if (A) close all upvalues >= R(A - 1)	*/
 					pc  += (i>>>14)-0x1ffff;
 					if (a > 0) {
 						for (--a, b = openups.length; --b>=0; )
@@ -405,7 +417,7 @@ public class LuaClosure extends LuaFunction {
 					{
 			            LuaValue limit = stack[a + 1];
 						LuaValue step  = stack[a + 2];
-						LuaValue idx   = step.add(stack[a]);
+						LuaValue idx   = stack[a].add(step);
 			            if (step.gt_b(0)? idx.lteq_b(limit): idx.gteq_b(limit)) {
 		                    stack[a] = idx;
 		                    stack[a + 3] = idx;
@@ -537,8 +549,24 @@ public class LuaClosure extends LuaFunction {
 	}
 	private void processErrorHooks(LuaError le, Prototype p, int pc) {
-		le.fileline = (p.source != null? p.source.tojstring(): "?") + ":" 
+		String file = "?";
-			+ (p.lineinfo != null && pc >= 0 && pc < p.lineinfo.length? String.valueOf(p.lineinfo[pc]): "?");
+		int line = -1;
 		{
 			CallFrame frame = null;
 			if (globals != null && globals.debuglib != null) {
 				frame = globals.debuglib.getCallFrame(le.level);
 				if (frame != null) {
 					String src = frame.shortsource();
 					file = src != null ? src : "?";
 					line = frame.currentline();
 				}
 			}
 			if (frame == null) {
 				file = p.source != null? p.source.tojstring(): "?";
 				line = p.lineinfo != null && pc >= 0 && pc < p.lineinfo.length ? p.lineinfo[pc] : -1;
 			}
 		}
 		le.fileline = file + ":" + line;
 		le.traceback = errorHook(le.getMessage(), le.level);
 	}
--- a/src/core/org/luaj/vm2/LuaDouble.java
+++ b/src/core/org/luaj/vm2/LuaDouble.java
@@ -177,7 +177,14 @@ public class LuaDouble extends LuaNumber {
 	 * @see #dmod_d(double, double)
 	 */
 	public static LuaValue dmod(double lhs, double rhs) {
-		return rhs!=0? valueOf( lhs-rhs*Math.floor(lhs/rhs) ): NAN;
+		if (rhs == 0 || lhs == Double.POSITIVE_INFINITY || lhs == Double.NEGATIVE_INFINITY) return NAN;
 		if (rhs == Double.POSITIVE_INFINITY) {
 			return lhs < 0 ? POSINF : valueOf(lhs);
 		}
 		if (rhs == Double.NEGATIVE_INFINITY) {
 			return lhs > 0 ? NEGINF : valueOf(lhs);
 		}
 		return valueOf( lhs-rhs*Math.floor(lhs/rhs) );
 	}
 	/** Take modulo for double numbers according to lua math, and return a double result.
@@ -188,32 +195,39 @@ public class LuaDouble extends LuaNumber {
 	 * @see #dmod(double, double)
 	 */
 	public static double dmod_d(double lhs, double rhs) {
-		return rhs!=0? lhs-rhs*Math.floor(lhs/rhs): Double.NaN;
+		if (rhs == 0 || lhs == Double.POSITIVE_INFINITY || lhs == Double.NEGATIVE_INFINITY) return Double.NaN;
 		if (rhs == Double.POSITIVE_INFINITY) {
 			return lhs < 0 ? Double.POSITIVE_INFINITY : lhs;
 		}
 		if (rhs == Double.NEGATIVE_INFINITY) {
 			return lhs > 0 ? Double.NEGATIVE_INFINITY : lhs;
 		}
 		return lhs-rhs*Math.floor(lhs/rhs);
 	}
 	// relational operators
-	public LuaValue   lt( LuaValue rhs )         { return rhs.gt_b(v)? LuaValue.TRUE: FALSE; }
+	public LuaValue   lt( LuaValue rhs )         { return rhs instanceof LuaNumber ? (rhs.gt_b(v)? TRUE: FALSE) : super.lt(rhs); }
 	public LuaValue   lt( double rhs )      { return v < rhs? TRUE: FALSE; }
 	public LuaValue   lt( int rhs )         { return v < rhs? TRUE: FALSE; }
-	public boolean lt_b( LuaValue rhs )       { return rhs.gt_b(v); }
+	public boolean lt_b( LuaValue rhs )       { return rhs instanceof LuaNumber ? rhs.gt_b(v) : super.lt_b(rhs); }
 	public boolean lt_b( int rhs )         { return v < rhs; }
 	public boolean lt_b( double rhs )      { return v < rhs; }
-	public LuaValue   lteq( LuaValue rhs )       { return rhs.gteq_b(v)? LuaValue.TRUE: FALSE; }
+	public LuaValue   lteq( LuaValue rhs )       { return rhs instanceof LuaNumber ? (rhs.gteq_b(v)? TRUE: FALSE) : super.lteq(rhs); }
 	public LuaValue   lteq( double rhs )    { return v <= rhs? TRUE: FALSE; }
 	public LuaValue   lteq( int rhs )       { return v <= rhs? TRUE: FALSE; }
-	public boolean lteq_b( LuaValue rhs )     { return rhs.gteq_b(v); }
+	public boolean lteq_b( LuaValue rhs )     { return rhs instanceof LuaNumber ? rhs.gteq_b(v) : super.lteq_b(rhs); }
 	public boolean lteq_b( int rhs )       { return v <= rhs; }
 	public boolean lteq_b( double rhs )    { return v <= rhs; }
-	public LuaValue   gt( LuaValue rhs )         { return rhs.lt_b(v)? LuaValue.TRUE: FALSE; }
+	public LuaValue   gt( LuaValue rhs )         { return rhs instanceof LuaNumber ? (rhs.lt_b(v)? TRUE: FALSE) : super.gt(rhs); }
 	public LuaValue   gt( double rhs )      { return v > rhs? TRUE: FALSE; }
 	public LuaValue   gt( int rhs )         { return v > rhs? TRUE: FALSE; }
-	public boolean gt_b( LuaValue rhs )       { return rhs.lt_b(v); }
+	public boolean gt_b( LuaValue rhs )       { return rhs instanceof LuaNumber ? rhs.lt_b(v) : super.gt_b(rhs); }
 	public boolean gt_b( int rhs )         { return v > rhs; }
 	public boolean gt_b( double rhs )      { return v > rhs; }
-	public LuaValue   gteq( LuaValue rhs )       { return rhs.lteq_b(v)? LuaValue.TRUE: FALSE; }
+	public LuaValue   gteq( LuaValue rhs )       { return rhs instanceof LuaNumber ? (rhs.lteq_b(v)? TRUE: FALSE) : super.gteq(rhs); }
 	public LuaValue   gteq( double rhs )    { return v >= rhs? TRUE: FALSE; }
 	public LuaValue   gteq( int rhs )       { return v >= rhs? TRUE: FALSE; }
-	public boolean gteq_b( LuaValue rhs )     { return rhs.lteq_b(v); }
+	public boolean gteq_b( LuaValue rhs )     { return rhs instanceof LuaNumber ? rhs.lteq_b(v) : super.gteq_b(rhs); }
 	public boolean gteq_b( int rhs )       { return v >= rhs; }
 	public boolean gteq_b( double rhs )    { return v >= rhs; }
--- a/src/core/org/luaj/vm2/LuaFunction.java
+++ b/src/core/org/luaj/vm2/LuaFunction.java
@@ -74,10 +74,13 @@ public class LuaFunction extends LuaValue {
 	/** Return the last part of the class name, to be used as a function name in tojstring and elsewhere.
 	 * @return String naming the last part of the class name after the last dot (.) or dollar sign ($).
 	 * If the first character is '_', it is skipped.
 	 */
 	public String classnamestub() {
 		String s = getClass().getName();
-		return s.substring(Math.max(s.lastIndexOf('.'),s.lastIndexOf('$'))+1);
+		int offset = Math.max(s.lastIndexOf('.'), s.lastIndexOf('$')) + 1;
 		if (s.charAt(offset) == '_') offset++;
 		return s.substring(offset);
 	}
 	/** Return a human-readable name for this function.  Returns the last part of the class name by default.
--- a/src/core/org/luaj/vm2/LuaInteger.java
+++ b/src/core/org/luaj/vm2/LuaInteger.java
@@ -172,28 +172,28 @@ public class LuaInteger extends LuaNumber {
 	public LuaValue   modFrom( double lhs )   { return LuaDouble.dmod(lhs,v); }
 	// relational operators
-	public LuaValue   lt( LuaValue rhs )         { return rhs.gt_b(v)? TRUE: FALSE; }	
+	public LuaValue   lt( LuaValue rhs )         { return rhs instanceof LuaNumber ? (rhs.gt_b(v)? TRUE: FALSE) : super.lt(rhs); }
 	public LuaValue   lt( double rhs )      { return v < rhs? TRUE: FALSE; }
 	public LuaValue   lt( int rhs )         { return v < rhs? TRUE: FALSE; }
-	public boolean lt_b( LuaValue rhs )       { return rhs.gt_b(v); }
+	public boolean lt_b( LuaValue rhs )       { return rhs instanceof LuaNumber ? rhs.gt_b(v) : super.lt_b(rhs); }
 	public boolean lt_b( int rhs )         { return v < rhs; }
 	public boolean lt_b( double rhs )      { return v < rhs; }
-	public LuaValue   lteq( LuaValue rhs )       { return rhs.gteq_b(v)? TRUE: FALSE; }
+	public LuaValue   lteq( LuaValue rhs )       { return rhs instanceof LuaNumber ? (rhs.gteq_b(v)? TRUE: FALSE) : super.lteq(rhs); }
 	public LuaValue   lteq( double rhs )    { return v <= rhs? TRUE: FALSE; }
 	public LuaValue   lteq( int rhs )       { return v <= rhs? TRUE: FALSE; }
-	public boolean lteq_b( LuaValue rhs )     { return rhs.gteq_b(v); }
+	public boolean lteq_b( LuaValue rhs )     { return rhs instanceof LuaNumber ? rhs.gteq_b(v) : super.lteq_b(rhs); }
 	public boolean lteq_b( int rhs )       { return v <= rhs; }
 	public boolean lteq_b( double rhs )    { return v <= rhs; }
-	public LuaValue   gt( LuaValue rhs )         { return rhs.lt_b(v)? TRUE: FALSE; }
+	public LuaValue   gt( LuaValue rhs )         { return rhs instanceof LuaNumber ? (rhs.lt_b(v)? TRUE: FALSE) : super.gt(rhs); }
 	public LuaValue   gt( double rhs )      { return v > rhs? TRUE: FALSE; }
 	public LuaValue   gt( int rhs )         { return v > rhs? TRUE: FALSE; }
-	public boolean gt_b( LuaValue rhs )       { return rhs.lt_b(v); }
+	public boolean gt_b( LuaValue rhs )       { return rhs instanceof LuaNumber ? rhs.lt_b(v) : super.gt_b(rhs); }
 	public boolean gt_b( int rhs )         { return v > rhs; }
 	public boolean gt_b( double rhs )      { return v > rhs; }
-	public LuaValue   gteq( LuaValue rhs )       { return rhs.lteq_b(v)? TRUE: FALSE; }
+	public LuaValue   gteq( LuaValue rhs )       { return rhs instanceof LuaNumber ? (rhs.lteq_b(v)? TRUE: FALSE) : super.gteq(rhs); }
 	public LuaValue   gteq( double rhs )    { return v >= rhs? TRUE: FALSE; }
 	public LuaValue   gteq( int rhs )       { return v >= rhs? TRUE: FALSE; }
-	public boolean gteq_b( LuaValue rhs )     { return rhs.lteq_b(v); }
+	public boolean gteq_b( LuaValue rhs )     { return rhs instanceof LuaNumber ? rhs.lteq_b(v) : super.gteq_b(rhs); }
 	public boolean gteq_b( int rhs )       { return v >= rhs; }
 	public boolean gteq_b( double rhs )    { return v >= rhs; }
--- a/src/core/org/luaj/vm2/LuaString.java
+++ b/src/core/org/luaj/vm2/LuaString.java
@@ -144,7 +144,7 @@ public class LuaString extends LuaValue {
 	/** Construct a new LuaString using a copy of the bytes array supplied */
 	private static LuaString valueFromCopy(byte[] bytes, int off, int len) {
 		final byte[] copy = new byte[len];
-		for (int i=0; i<len; ++i) copy[i] = bytes[off+i];
+		System.arraycopy(bytes, off, copy, 0, len);
 		return new LuaString(copy, 0, len);
 	}
@@ -289,20 +289,20 @@ public class LuaString extends LuaValue {
 	public LuaValue   modFrom( double lhs )    { return LuaDouble.dmod(lhs, checkarith()); }
 	// relational operators, these only work with other strings
-	public LuaValue   lt( LuaValue rhs )         { return rhs.strcmp(this)>0? LuaValue.TRUE: FALSE; }
+	public LuaValue   lt( LuaValue rhs )         { return rhs.isstring() ? (rhs.strcmp(this)>0? LuaValue.TRUE: FALSE) : super.lt(rhs); }
-	public boolean lt_b( LuaValue rhs )       { return rhs.strcmp(this)>0; }
+	public boolean lt_b( LuaValue rhs )       { return rhs.isstring() ? rhs.strcmp(this)>0 : super.lt_b(rhs); }
 	public boolean lt_b( int rhs )         { typerror("attempt to compare string with number"); return false; }
 	public boolean lt_b( double rhs )      { typerror("attempt to compare string with number"); return false; }
-	public LuaValue   lteq( LuaValue rhs )       { return rhs.strcmp(this)>=0? LuaValue.TRUE: FALSE; }
+	public LuaValue   lteq( LuaValue rhs )       { return rhs.isstring() ? (rhs.strcmp(this)>=0? LuaValue.TRUE: FALSE) : super.lteq(rhs); }
-	public boolean lteq_b( LuaValue rhs )     { return rhs.strcmp(this)>=0; }
+	public boolean lteq_b( LuaValue rhs )     { return rhs.isstring() ? rhs.strcmp(this)>=0 : super.lteq_b(rhs); }
 	public boolean lteq_b( int rhs )       { typerror("attempt to compare string with number"); return false; }
 	public boolean lteq_b( double rhs )    { typerror("attempt to compare string with number"); return false; }
-	public LuaValue   gt( LuaValue rhs )         { return rhs.strcmp(this)<0? LuaValue.TRUE: FALSE; }
+	public LuaValue   gt( LuaValue rhs )         { return rhs.isstring() ? (rhs.strcmp(this)<0? LuaValue.TRUE: FALSE) : super.gt(rhs); }
-	public boolean gt_b( LuaValue rhs )       { return rhs.strcmp(this)<0; }
+	public boolean gt_b( LuaValue rhs )       { return rhs.isstring() ? rhs.strcmp(this)<0 : super.gt_b(rhs); }
 	public boolean gt_b( int rhs )         { typerror("attempt to compare string with number"); return false; }
 	public boolean gt_b( double rhs )      { typerror("attempt to compare string with number"); return false; }
-	public LuaValue   gteq( LuaValue rhs )       { return rhs.strcmp(this)<=0? LuaValue.TRUE: FALSE; }
+	public LuaValue   gteq( LuaValue rhs )       { return rhs.isstring() ? (rhs.strcmp(this)<=0? LuaValue.TRUE: FALSE) : super.gteq(rhs); }
-	public boolean gteq_b( LuaValue rhs )     { return rhs.strcmp(this)<=0; }
+	public boolean gteq_b( LuaValue rhs )     { return rhs.isstring() ? rhs.strcmp(this)<=0 : super.gteq_b(rhs); }
 	public boolean gteq_b( int rhs )       { typerror("attempt to compare string with number"); return false; }
 	public boolean gteq_b( double rhs )    { typerror("attempt to compare string with number"); return false; }
@@ -391,23 +391,23 @@ public class LuaString extends LuaValue {
 	public short   toshort()       { return (short) toint(); }
 	public double optdouble(double defval) {
-		return checknumber().checkdouble();
+		return checkdouble();
 	}
 	public int optint(int defval) {
-		return checknumber().checkint();
+		return checkint();
 	}
 	public LuaInteger optinteger(LuaInteger defval) {
-		return checknumber().checkinteger();
+		return checkinteger();
 	}
 	public long optlong(long defval) {
-		return checknumber().checklong();
+		return checklong();
 	}
 	public LuaNumber optnumber(LuaNumber defval) {
-		return checknumber().checknumber();
+		return checknumber();
 	}
 	public LuaString optstring(LuaString defval) {
--- a/src/core/org/luaj/vm2/LuaTable.java
+++ b/src/core/org/luaj/vm2/LuaTable.java
@@ -266,8 +266,8 @@ public class LuaTable extends LuaValue implements Metatable {
 	/** caller must ensure key is not nil */
 	public void set( LuaValue key, LuaValue value ) {
-		if (!key.isvalidkey() && !metatag(NEWINDEX).isfunction())
+		if (key == null || !key.isvalidkey() && !metatag(NEWINDEX).isfunction())
-			typerror("table index");
+			throw new LuaError("value ('" + key + "') can not be used as a table index");
 		if ( m_metatable==null || ! rawget(key).isnil() ||  ! settable(this,key,value) )
 			rawset(key, value);
 	}
@@ -299,15 +299,15 @@ public class LuaTable extends LuaValue implements Metatable {
 	 * @return The removed item, or {@link #NONE} if not removed
 	 */
 	public LuaValue remove(int pos) {
-		int n = rawlen();
+		int n = length();
 		if ( pos == 0 )
 			pos = n;
 		else if (pos > n)
 			return NONE;
-		LuaValue v = rawget(pos);
+		LuaValue v = get(pos);
 		for ( LuaValue r=v; !r.isnil(); ) {
-			r = rawget(pos+1);
+			r = get(pos+1);
-			rawset(pos++, r);
+			set(pos++, r);
 		}
 		return v.isnil()? NONE: v;
 	}
@@ -319,10 +319,10 @@ public class LuaTable extends LuaValue implements Metatable {
 	 */
 	public void insert(int pos, LuaValue value) {
 		if ( pos == 0 )
-			pos = rawlen()+1;
+			pos = length()+1;
 		while ( ! value.isnil() ) {
-			LuaValue v = rawget( pos );
+			LuaValue v = get( pos );
-			rawset(pos++, value);
+			set(pos++, value);
 			value = v;
 		}
 	}
@@ -347,7 +347,12 @@ public class LuaTable extends LuaValue implements Metatable {
 	}
 	public int length() {
-		return m_metatable != null? len().toint(): rawlen(); 
+		if (m_metatable != null) {
 			LuaValue len = len();
 			if (!len.isint()) throw new LuaError("table length is not an integer: " + len);
 			return len.toint();
 		}
 		return rawlen();
 	}
 	public LuaValue len()  {
@@ -390,7 +395,7 @@ public class LuaTable extends LuaValue implements Metatable {
 					}
 				}
 				if ( hash.length == 0 )
-					error( "invalid key to 'next'" );
+					error( "invalid key to 'next' 1: " + key );
 				i = hashSlot( key );
 				boolean found = false;
 				for ( Slot slot = hash[i]; slot != null; slot = slot.rest() ) {
@@ -404,7 +409,7 @@ public class LuaTable extends LuaValue implements Metatable {
 					}
 				}
 				if ( !found ) {
-					error( "invalid key to 'next'" );
+					error( "invalid key to 'next' 2: " + key );
 				}
 				i += 1+array.length;
 			}
@@ -467,7 +472,8 @@ public class LuaTable extends LuaValue implements Metatable {
 				}
 			}
 			if ( checkLoadFactor() ) {
-				if ( key.isinttype() && key.toint() > 0 ) {
+				if ( (m_metatable == null || !m_metatable.useWeakValues())
 					&& key.isinttype() && key.toint() > 0 ) {
 					// a rehash might make room in the array portion for this key.
 					rehash( key.toint() );
 					if ( arrayset(key.toint(), value) )
@@ -714,7 +720,7 @@ public class LuaTable extends LuaValue implements Metatable {
 					StrongSlot entry = slot.first();
 					if (entry != null)
 						newArray[ k - 1 ] = entry.value();
-				} else {
+				} else if ( !(slot instanceof DeadSlot) ) {
 					int j = slot.keyindex( newHashMask );
 					newHash[j] = slot.relink( newHash[j] );
 				}
@@ -780,36 +786,39 @@ public class LuaTable extends LuaValue implements Metatable {
 	 * @param comparator {@link LuaValue} to be called to compare elements.
 	 */
 	public void sort(LuaValue comparator) {
 		if (len().tolong() >= (long)Integer.MAX_VALUE) throw new LuaError("array too big: " + len().tolong());
 		if (m_metatable != null && m_metatable.useWeakValues()) {
 			dropWeakArrayValues();
 		}
-		int n = array.length;
+		int n = length();
 		while ( n > 0 && array[n-1] == null )
 			--n;
 		if ( n > 1 )
-			heapSort(n, comparator);
+			heapSort(n, comparator.isnil() ? null : comparator);
 	}
 	private void heapSort(int count, LuaValue cmpfunc) {
 		heapify(count, cmpfunc);
-		for ( int end=count-1; end>0; ) {
+		for ( int end=count; end>1; ) {
-			swap(end, 0);
+			LuaValue a = get(end); // swap(end, 1)
-			siftDown(0, --end, cmpfunc);
+			set(end, get(1));
 			set(1, a);
 			siftDown(1, --end, cmpfunc);
 		}
 	}
 	private void heapify(int count, LuaValue cmpfunc) {
-		for ( int start=count/2-1; start>=0; --start )
+		for ( int start=count/2; start>0; --start )
-			siftDown(start, count - 1, cmpfunc);
+			siftDown(start, count, cmpfunc);
 	}
 	private void siftDown(int start, int end, LuaValue cmpfunc) {
-		for ( int root=start; root*2+1 <= end; ) { 
+		for ( int root=start; root*2 <= end; ) {
-			int child = root*2+1; 
+			int child = root*2;
 			if (child < end && compare(child, child + 1, cmpfunc))
 				++child;
 			if (compare(root, child, cmpfunc)) {
-				swap(root, child);
+				LuaValue a = get(root); // swap(root, child)
 				set(root, get(child));
 				set(child, a);
 				root = child;
 			} else
 				return;
@@ -817,29 +826,16 @@ public class LuaTable extends LuaValue implements Metatable {
 	}
 	private boolean compare(int i, int j, LuaValue cmpfunc) {
-		LuaValue a, b;
+		LuaValue a = get(i), b = get(j);
 		if (m_metatable == null) {
 			a = array[i];
 			b = array[j];
 		} else {
 			a = m_metatable.arrayget(array, i);
 			b = m_metatable.arrayget(array, j);
 		}
 		if ( a == null || b == null )
 			return false;
-		if ( ! cmpfunc.isnil() ) {
+		if ( cmpfunc != null ) {
 			return cmpfunc.call(a,b).toboolean();
 		} else {
 			return a.lt_b(b);
 		}
 	}
 	private void swap(int i, int j) {
 		LuaValue a = array[i];
 		array[i] = array[j];
 		array[j] = a;
 	}
 	/** This may be deprecated in a future release.
 	 * It is recommended to count via iteration over next() instead
 	 * @return count of keys in the table
@@ -892,6 +888,11 @@ public class LuaTable extends LuaValue implements Metatable {
 	/** Unpack the elements from i to j inclusive */
 	public Varargs unpack(int i, int j) {
 		if (j < i) return NONE;
 		int count = j - i;
 		if (count < 0) throw new LuaError("too many results to unpack: greater " + Integer.MAX_VALUE); // integer overflow
 		int max = 0x00ffffff;
 		if (count >= max) throw new LuaError("too many results to unpack: " + count + " (max is " + max + ')');
 		int n = j + 1 - i;
 		switch (n) {
 		case 0: return NONE;
@@ -900,10 +901,14 @@ public class LuaTable extends LuaValue implements Metatable {
 		default:
 			if (n < 0)
 				return NONE;
 			try {
 				LuaValue[] v = new LuaValue[n];
 				while (--n >= 0)
 					v[n] = get(i+n);
 				return varargsOf(v);
 			} catch (OutOfMemoryError e) {
 				throw new LuaError("too many results to unpack [out of memory]: " + n);
 			}
 		}
 	}
@@ -1231,14 +1236,15 @@ public class LuaTable extends LuaValue implements Metatable {
 		}
 		public Entry set(LuaValue value) {
 			if (value.type() == TNUMBER) {
 				LuaValue n = value.tonumber();
 				if (!n.isnil()) {
 					this.value = n.todouble();
 					return this;
 			} else {
 				return new NormalEntry( this.key, value );
 				}
 			}
 			return new NormalEntry( this.key, value );
 		}
 		public int keyindex( int mask ) {
 			return hashSlot( key, mask );
--- a/src/core/org/luaj/vm2/LuaValue.java
+++ b/src/core/org/luaj/vm2/LuaValue.java
@@ -21,8 +21,6 @@
 ******************************************************************************/
 package org.luaj.vm2;
 import org.luaj.vm2.Varargs;
 /**
 * Base class for all concrete lua type values.
 * <p>
@@ -643,7 +641,7 @@ public class LuaValue extends Varargs {
 	 * @see #isnumber()
 	 * @see #TNUMBER
 	 */
-	public double      optdouble(double defval)            { argerror("double");    return 0;     }
+	public double      optdouble(double defval)            { argerror("number");    return 0;     }
 	/** Check that optional argument is a function and return as {@link LuaFunction}
 	 * <p>
@@ -855,7 +853,7 @@ public class LuaValue extends Varargs {
 	 * @see #optdouble(double)
 	 * @see #TNUMBER
 	 */
-	public double      checkdouble()           { argerror("double");    return 0; }
+	public double      checkdouble()           { argerror("number");    return 0; }
 	/** Check that the value is a function , or throw {@link LuaError} if not
 	 * <p>
@@ -2045,7 +2043,7 @@ public class LuaValue extends Varargs {
 	 * @see #eqmtcall(LuaValue, LuaValue, LuaValue, LuaValue)
 	 * @see #EQ
 	 */
-	public LuaValue   eq( LuaValue val )      { return this == val? TRUE: FALSE; }
+	public LuaValue   eq( LuaValue val )      { return eq_b(val)? TRUE: FALSE; }
 	/** Equals: Perform equality comparison with another value
 	 * including metatag processing using {@link #EQ},
@@ -3143,7 +3141,7 @@ public class LuaValue extends Varargs {
 	 * @return {@link LuaString} corresponding to the value if a string or number
 	 * @throws LuaError if not a string or number
 	 */
-	public LuaString strvalue()     { typerror("strValue"); return null; }
+	public LuaString strvalue()     { typerror("string or number"); return null; }
 	/** Return this value as a strong reference, or null if it was weak and is no longer referenced.
 	 * @return {@link LuaValue} referred to, or null if it was weak and is no longer referenced.
@@ -3298,7 +3296,7 @@ public class LuaValue extends Varargs {
 				if ((!res.isnil()) || (tm = t.metatag(INDEX)).isnil())
 					return res;
 			} else if ((tm = t.metatag(INDEX)).isnil())
-				t.indexerror();
+				t.indexerror(key.tojstring());
 			if (tm.isfunction())
 				return tm.call(t, key);
 			t = tm;
@@ -3326,7 +3324,7 @@ public class LuaValue extends Varargs {
 					return true;
 				}
 			} else if ((tm = t.metatag(NEWINDEX)).isnil())
-				t.typerror("index");
+				throw new LuaError("table expected for set index ('" + key + "') value, got " + t.typename());
 			if (tm.isfunction()) {
 				tm.call(t, key, value);
 				return true;
@@ -3362,7 +3360,7 @@ public class LuaValue extends Varargs {
 	protected LuaValue checkmetatag(LuaValue tag, String reason) {
 		LuaValue h = this.metatag(tag);
 		if ( h.isnil() )
-			throw new LuaError(reason+typename());
+			throw new LuaError(reason + "a " + typename() + " value");
 		return h;
 	}
@@ -3389,8 +3387,8 @@ public class LuaValue extends Varargs {
 	/** Throw {@link LuaError} indicating index was attempted on illegal type
 	 * @throws LuaError when called.
 	 */
-    private void indexerror() {
+    private void indexerror(String key) {
-		error( "attempt to index ? (a "+typename()+" value)" );
+		error( "attempt to index ? (a "+typename()+" value) with key '" + key + "'" );
 	}
 	/** Construct a {@link Varargs} around an array of {@link LuaValue}s.
--- a/src/core/org/luaj/vm2/Print.java
+++ b/src/core/org/luaj/vm2/Print.java
@@ -128,6 +128,10 @@ public class Print extends Lua {
 	}
 	static void printValue( PrintStream ps, LuaValue v ) {
 		if (v == null) {
 			ps.print("null");
 			return;
 		}
 		switch ( v.type() ) {
 		case LuaValue.TSTRING: printString( ps, (LuaString) v ); break;
 		default: ps.print( v.tojstring() );
@@ -136,7 +140,7 @@ public class Print extends Lua {
 	}
 	static void printConstant(PrintStream ps, Prototype f, int i) {
-		printValue( ps, f.k[i] );
+		printValue( ps, i < f.k.length ? f.k[i] : LuaValue.valueOf("UNKNOWN_CONST_" + i) );
 	}
 	static void printUpvalue(PrintStream ps, Upvaldesc u) {
@@ -152,7 +156,7 @@ public class Print extends Lua {
 		int[] code = f.code;
 		int pc, n = code.length;
 		for (pc = 0; pc < n; pc++) {
-			printOpCode(f, pc);
+			pc = printOpCode(f, pc);
 			ps.println();
 		}
 	}
@@ -161,9 +165,10 @@ public class Print extends Lua {
 	 * Print an opcode in a prototype
 	 * @param f the {@link Prototype}
 	 * @param pc the program counter to look up and print
 	 * @return pc same as above or changed
 	 */
-	public static void printOpCode(Prototype f, int pc) {
+	public static int printOpCode(Prototype f, int pc) {
-		printOpCode(ps,f,pc);
+		return printOpCode(ps,f,pc);
 	}
 	/** 
@@ -171,8 +176,9 @@ public class Print extends Lua {
 	 * @param ps the {@link PrintStream} to print to
 	 * @param f the {@link Prototype}
 	 * @param pc the program counter to look up and print
 	 * @return pc same as above or changed
 	 */
-	public static void printOpCode(PrintStream ps, Prototype f, int pc) {
+	public static int printOpCode(PrintStream ps, Prototype f, int pc) {
 		int[] code = f.code;
 		int i = code[pc];
 		int o = GET_OPCODE(i);
@@ -187,6 +193,9 @@ public class Print extends Lua {
 			ps.print("[" + line + "]  ");
 		else
 			ps.print("[-]  ");
 		if (o >= OPNAMES.length - 1) {
 			ps.print("UNKNOWN_OP_" + o + "  ");
 		} else {
 			ps.print(OPNAMES[o] + "  ");
 			switch (getOpMode(o)) {
 			case iABC:
@@ -218,11 +227,19 @@ public class Print extends Lua {
 			case OP_GETUPVAL:
 			case OP_SETUPVAL:
 				ps.print("  ; ");
 				if (b < f.upvalues.length) {
 					printUpvalue(ps, f.upvalues[b]);
 				} else {
 					ps.print("UNKNOWN_UPVALUE_" + b);
 				}	
 				break;
 			case OP_GETTABUP:
 				ps.print("  ; ");
 				if (b < f.upvalues.length) {
 					printUpvalue(ps, f.upvalues[b]);
 				} else {
 					ps.print("UNKNOWN_UPVALUE_" + b);
 				}
 				ps.print(" ");
 				if (ISK(c))
 					printConstant(ps, f, INDEXK(c));
@@ -231,7 +248,11 @@ public class Print extends Lua {
 				break;
 			case OP_SETTABUP:
 				ps.print("  ; ");
 				if (a < f.upvalues.length) {
 					printUpvalue(ps, f.upvalues[a]);
 				} else {
 					ps.print("UNKNOWN_UPVALUE_" + a);
 				}
 				ps.print(" ");
 				if (ISK(b))
 					printConstant(ps, f, INDEXK(b));
@@ -278,11 +299,15 @@ public class Print extends Lua {
 				ps.print("  ; to " + (sbx + pc + 2));
 				break;
 			case OP_CLOSURE:
 				if (bx < f.p.length) {
 					ps.print("  ; " + f.p[bx].getClass().getName());
 				} else {
 					ps.print("  ; UNKNOWN_PROTYPE_" + bx);
 				}
 				break;
 			case OP_SETLIST:
 				if (c == 0)
-				ps.print("  ; " + ((int) code[++pc]));
+					ps.print("  ; " + ((int) code[++pc]) + " (stored in the next OP)");
 				else
 					ps.print("  ; " + ((int) c));
 				break;
@@ -293,6 +318,8 @@ public class Print extends Lua {
 				break;
 			}
 		}
 		return pc;
 	}
 	private static int getline(Prototype f, int pc) {
 		return pc>0 && f.lineinfo!=null && pc<f.lineinfo.length? f.lineinfo[pc]: -1;
--- a/src/core/org/luaj/vm2/Varargs.java
+++ b/src/core/org/luaj/vm2/Varargs.java
@@ -291,7 +291,7 @@ public abstract class Varargs {
 	 * @return java double value if argument i is a number or string that converts to a number
 	 * @exception LuaError if the argument is not a number
 	 * */
-	public double       checkdouble(int i)           { return arg(i).checknumber().todouble(); }
+	public double       checkdouble(int i)           { return arg(i).checkdouble(); }
 	/** Return argument i as a function, or throw an error if an incompatible type.
 	 * @param i the index of the argument to test, 1 is the first argument
@@ -300,12 +300,12 @@ public abstract class Varargs {
 	 * */
 	public LuaFunction    checkfunction(int i)         { return arg(i).checkfunction(); }
-	/** Return argument i as a java int value, discarding any fractional part, or throw an error if not a number.
+	/** Return argument i as a java int value, or throw an error if it cannot be converted to one.
 	 * @param i the index of the argument to test, 1 is the first argument
-	 * @return int value with fraction discarded and truncated if necessary if argument i is number
+	 * @return int value if argument i is a number or string that converts to a number
-	 * @exception LuaError if the argument is not a number
+	 * @exception LuaError if the argument cannot be represented by a java int value
 	 * */
-	public int          checkint(int i)              { return arg(i).checknumber().toint(); }
+	public int          checkint(int i)              { return arg(i).checkint(); }
 	/** Return argument i as a java int value, or throw an error if not a number or is not representable by a java int.
 	 * @param i the index of the argument to test, 1 is the first argument
@@ -314,12 +314,12 @@ public abstract class Varargs {
 	 * */
 	public LuaInteger   checkinteger(int i)          { return arg(i).checkinteger(); }
-	/** Return argument i as a java long value, discarding any fractional part, or throw an error if not a number.
+	/** Return argument i as a java long value, or throw an error if it cannot be converted to one.
 	 * @param i the index of the argument to test, 1 is the first argument
-	 * @return long value with fraction discarded and truncated if necessary if argument i is number
+	 * @return long value if argument i is a number or string that converts to a number
-	 * @exception LuaError if the argument is not a number
+	 * @exception LuaError if the argument cannot be represented by a java long value
 	 * */
-	public long         checklong(int i)             { return arg(i).checknumber().tolong(); }
+	public long         checklong(int i)             { return arg(i).checklong(); }
 	/** Return argument i as a LuaNumber, or throw an error if not a number or string that can be converted to a number.
 	 * @param i the index of the argument to test, 1 is the first argument
@@ -707,8 +707,10 @@ public abstract class Varargs {
 	/** Return Varargs that cannot be using a shared array for the storage, and is flattened.
 	 * Internal utility method not intended to be called directly from user code.
 	 * @return Varargs containing same values, but flattened and with a new array if needed.
 	 * @exclude
 	 * @hide
 	 */
-	Varargs dealias() {
+	public Varargs dealias() {
 		int n = narg();
 		switch (n) {
 		case 0: return LuaValue.NONE;
--- a/src/core/org/luaj/vm2/compiler/Constants.java
+++ b/src/core/org/luaj/vm2/compiler/Constants.java
@@ -105,6 +105,11 @@ public class Constants extends Lua {
 				((bc << POS_Bx) & MASK_Bx) ;
 	}
 	static int CREATE_Ax(int o, int a) {
 		return ((o << POS_OP) & MASK_OP) |
 				((a << POS_Ax) & MASK_Ax) ;
 	}
 	// vector reallocation
 	static LuaValue[] realloc(LuaValue[] v, int n) {
--- a/src/core/org/luaj/vm2/compiler/DumpState.java
+++ b/src/core/org/luaj/vm2/compiler/DumpState.java
@@ -28,9 +28,9 @@ import java.io.OutputStream;
 import org.luaj.vm2.Globals;
 import org.luaj.vm2.LoadState;
 import org.luaj.vm2.LocVars;
 import org.luaj.vm2.Prototype;
 import org.luaj.vm2.LuaString;
 import org.luaj.vm2.LuaValue;
 import org.luaj.vm2.Prototype;
 /** Class to dump a {@link Prototype} into an output stream, as part of compiling.
@@ -85,7 +85,7 @@ public class DumpState {
 	public static final int NUMBER_FORMAT_DEFAULT = NUMBER_FORMAT_FLOATS_OR_DOUBLES;
 	// header fields
-	private boolean IS_LITTLE_ENDIAN = false;
+	private boolean IS_LITTLE_ENDIAN = true;
 	private int NUMBER_FORMAT = NUMBER_FORMAT_DEFAULT;
 	private int SIZEOF_LUA_NUMBER = 8;
 	private static final int SIZEOF_INT = 4;
--- a/src/core/org/luaj/vm2/compiler/FuncState.java
+++ b/src/core/org/luaj/vm2/compiler/FuncState.java
@@ -50,7 +50,6 @@ public class FuncState extends Constants {
 	Hashtable h;  /* table to find (and reuse) elements in `k' */
 	FuncState prev;  /* enclosing function */
 	LexState ls;  /* lexical state */
 	LuaC.CompileState L;  /* compiler being invoked */
 	BlockCnt bl;  /* chain of current blocks */
 	int pc;  /* next position to code (equivalent to `ncode') */
 	int lasttarget;   /* `pc' of last `jump target' */
@@ -113,8 +112,8 @@ public class FuncState extends Constants {
 	void errorlimit (int limit, String what) {
 		// TODO: report message logic.
 	  	String msg = (f.linedefined == 0) ?
-	  	    L.pushfstring("main function has more than "+limit+" "+what) :
+	  	    ls.L.pushfstring("main function has more than "+limit+" "+what) :
-	  	    L.pushfstring("function at line "+f.linedefined+" has more than "+limit+" "+what);
+	  	    ls.L.pushfstring("function at line "+f.linedefined+" has more than "+limit+" "+what);
 	  	  ls.lexerror(msg, 0);
 	}
@@ -581,11 +580,11 @@ public class FuncState extends Constants {
 			break;
 		}
 		case LexState.VK: {
-			this.codeABx(OP_LOADK, reg, e.u.info);
+			this.codeK(reg, e.u.info);
 			break;
 		}
 		case LexState.VKNUM: {
-			this.codeABx(OP_LOADK, reg, this.numberK(e.u.nval()));
+			this.codeK(reg, this.numberK(e.u.nval()));
 			break;
 		}
 		case LexState.VRELOCABLE: {
@@ -1117,6 +1116,20 @@ public class FuncState extends Constants {
 		return this.code(CREATE_ABx(o, a, bc), this.ls.lastline);
 	}
 	int codeextraarg(int a) {
 		_assert(a <= MAXARG_Ax);
 		return this.code(CREATE_Ax(OP_EXTRAARG, a), this.ls.lastline);
 	}
 	int codeK(int reg, int k) {
 		if (k <= MAXARG_Bx)
 			return codeABx(OP_LOADK, reg, k);
 		else {
 			int p = codeABx(OP_LOADKX, reg, 0);
 			codeextraarg(k);
 			return p;
 		}
 	}
 	void setlist(int base, int nelems, int tostore) {
 		int c = (nelems - 1) / LFIELDS_PER_FLUSH + 1;
--- a/src/core/org/luaj/vm2/compiler/LexState.java
+++ b/src/core/org/luaj/vm2/compiler/LexState.java
@@ -198,7 +198,7 @@ public class LexState extends Constants {
 	}
 	private boolean isspace(int c) {
-		return (c <= ' ');
+		return (c >= 0 && c <= ' ');
 	}
@@ -388,8 +388,13 @@ public class LexState extends Constants {
 			seminfo.r = LuaValue.ZERO;
 		else if (str.indexOf('x')>=0 || str.indexOf('X')>=0)
 			seminfo.r = strx2number(str, seminfo);
-		else
+		else {
 			try {
 				seminfo.r = LuaValue.valueOf(Double.parseDouble(str.trim()));
 			} catch (NumberFormatException e) {
 				lexerror("malformed number (" + e.getMessage() + ")", TK_NUMBER);
 			}
 		}
 		return true;
 	}
@@ -408,7 +413,6 @@ public class LexState extends Constants {
 			else
 				break;
 		}
 		save('\0');
 		String str = new String(buff, 0, nbuff);
 		str2d(str, seminfo);
 	}
@@ -585,6 +589,13 @@ public class LexState extends Constants {
 				inclinenumber();
 				continue;
 			}
 			case ' ':
 			case '\f':
 			case '\t':
 			case 0x0B: /* \v */ {
 				nextChar();
 				continue;
 			}
 			case '-': {
 				nextChar();
 				if (current != '-')
@@ -688,19 +699,12 @@ public class LexState extends Constants {
 				return TK_EOS;
 			}
 			default: {
-				if (isspace(current)) {
+				if (isalpha(current) || current == '_') {
 					_assert (!currIsNewline());
 					nextChar();
 					continue;
 				} else if (isdigit(current)) {
 					read_numeral(seminfo);
 					return TK_NUMBER;
 				} else if (isalpha(current) || current == '_') {
 					/* identifier or reserved word */
 					LuaString ts;
 					do {
 						save_and_next();
-					} while (isalnum(current) || current == '_');
+					} while (isalnum(current));
 					ts = newstring(buff, 0, nbuff);
 					if ( RESERVED.containsKey(ts) )
 						return ((Integer)RESERVED.get(ts)).intValue();
@@ -1744,7 +1748,7 @@ public class LexState extends Constants {
 		fs.checkrepeated(dyd.label, dyd.n_label, label);  /* check for repeated labels */
 		checknext(TK_DBCOLON);  /* skip double colon */
 		/* create new entry for this label */
-		l = newlabelentry(dyd.label=grow(dyd.label, dyd.n_label+1), dyd.n_label++, label, line, fs.pc);
+		l = newlabelentry(dyd.label=grow(dyd.label, dyd.n_label+1), dyd.n_label++, label, line, fs.getlabel());
 		skipnoopstat();  /* skip other no-op statements */
 		if (block_follow(false)) {  /* label is last no-op statement in the block? */
 			/* assume that locals are already out of scope */
@@ -1845,7 +1849,7 @@ public class LexState extends Constants {
 		if (this.testnext(','))
 			this.exp1(); /* optional step */
 		else { /* default step = 1 */
-			fs.codeABx(Lua.OP_LOADK, fs.freereg, fs.numberK(LuaInteger.valueOf(1)));
+			fs.codeK(fs.freereg, fs.numberK(LuaInteger.valueOf(1)));
 			fs.reserveregs(1);
 		}
 		this.forbody(base, line, 1, true);
--- a/src/core/org/luaj/vm2/compiler/LuaC.java
+++ b/src/core/org/luaj/vm2/compiler/LuaC.java
@@ -117,7 +117,7 @@ public class LuaC extends Constants implements Globals.Compiler, Globals.Loader
 		protected CompileState() {}
 		/** Parse the input */
-		private Prototype luaY_parser(InputStream z, String name) throws IOException{
+		Prototype luaY_parser(InputStream z, String name) throws IOException{
 			LexState lexstate = new LexState(this, z);
 			FuncState funcstate = new FuncState();
 			// lexstate.buff = buff;
--- a/src/core/org/luaj/vm2/lib/BaseLib.java
+++ b/src/core/org/luaj/vm2/lib/BaseLib.java
@@ -152,7 +152,7 @@ public class BaseLib extends TwoArgFunction implements ResourceFinder {
 				System.gc();
 				return LuaValue.TRUE;
 			} else {
-				this.argerror("gc op");
+				argerror(1, "invalid option '" + s + "'");
 			}
 			return NIL;
 		}
@@ -173,16 +173,16 @@ public class BaseLib extends TwoArgFunction implements ResourceFinder {
 	// "error", // ( message [,level] ) -> ERR
 	static final class error extends TwoArgFunction {
 		public LuaValue call(LuaValue arg1, LuaValue arg2) {
-			throw arg1.isnil()? new LuaError(null, arg2.optint(1)): 
+			if (arg1.isnil()) throw new LuaError(NIL);
-				arg1.isstring()? new LuaError(arg1.tojstring(), arg2.optint(1)): 
+			if (!arg1.isstring() || arg2.optint(1) == 0) throw new LuaError(arg1);
-					new LuaError(arg1);
+			throw new LuaError(arg1.tojstring(), arg2.optint(1));
 		}
 	}
 	// "getmetatable", // ( object ) -> table
 	static final class getmetatable extends LibFunction {
 		public LuaValue call() {
-			return argerror(1, "value");
+			return argerror(1, "value expected");
 		}
 		public LuaValue call(LuaValue arg) {
 			LuaValue mt = arg.getmetatable();
@@ -193,7 +193,9 @@ public class BaseLib extends TwoArgFunction implements ResourceFinder {
 	final class load extends VarArgFunction {
 		public Varargs invoke(Varargs args) {
 			LuaValue ld = args.arg1();
-			args.argcheck(ld.isstring() || ld.isfunction(), 1, "ld must be string or function");
+			if (!ld.isstring() && !ld.isfunction()) {
 				throw new LuaError("bad argument #1 to 'load' (string or function expected, got " + ld.typename() + ")");
 			}
 			String source = args.optjstring(2, ld.isstring()? ld.tojstring(): "=(load)");
 			String mode = args.optjstring(3, "bt");
 			LuaValue env = args.optvalue(4, globals);
@@ -249,7 +251,7 @@ public class BaseLib extends TwoArgFunction implements ResourceFinder {
 				LuaString s = tostring.call( args.arg(i) ).strvalue();
 				globals.STDOUT.print(s.tojstring());
 			}
-			globals.STDOUT.println();
+			globals.STDOUT.print('\n');
 			return NONE;
 		}
 	}
@@ -258,10 +260,10 @@ public class BaseLib extends TwoArgFunction implements ResourceFinder {
 	// "rawequal", // (v1, v2) -> boolean
 	static final class rawequal extends LibFunction {
 		public LuaValue call() {
-			return argerror(1, "value");
+			return argerror(1, "value expected");
 		}
 		public LuaValue call(LuaValue arg) {
-			return argerror(2, "value");
+			return argerror(2, "value expected");
 		}
 		public LuaValue call(LuaValue arg1, LuaValue arg2) {
 			return valueOf(arg1.raweq(arg2));
@@ -269,12 +271,9 @@ public class BaseLib extends TwoArgFunction implements ResourceFinder {
 	}
 	// "rawget", // (table, index) -> value
-	static final class rawget extends LibFunction {
+	static final class rawget extends TableLibFunction {
 		public LuaValue call() {
 			return argerror(1, "value");
 		}
 		public LuaValue call(LuaValue arg) {
-			return argerror(2, "value");
+			return argerror(2, "value expected");
 		}
 		public LuaValue call(LuaValue arg1, LuaValue arg2) {
 			return arg1.checktable().rawget(arg2);
@@ -290,16 +289,17 @@ public class BaseLib extends TwoArgFunction implements ResourceFinder {
 	}
 	// "rawset", // (table, index, value) -> table
-	static final class rawset extends LibFunction {
+	static final class rawset extends TableLibFunction {
 		public LuaValue call(LuaValue table) {
-			return argerror(2,"value");
+			return argerror(2,"value expected");
 		}
 		public LuaValue call(LuaValue table, LuaValue index) {
-			return argerror(3,"value");
+			return argerror(3,"value expected");
 		}
 		public LuaValue call(LuaValue table, LuaValue index, LuaValue value) {
 			LuaTable t = table.checktable();
-			t.rawset(index.checknotnil(), value);
+			if (!index.isvalidkey()) argerror(2, "table index is nil");
 			t.rawset(index, value);
 			return t;
 		}
 	}
@@ -318,9 +318,9 @@ public class BaseLib extends TwoArgFunction implements ResourceFinder {
 	}
 	// "setmetatable", // (table, metatable) -> table
-	static final class setmetatable extends LibFunction {
+	static final class setmetatable extends TableLibFunction {
 		public LuaValue call(LuaValue table) {
-			return argerror(2,"value");
+			return argerror(2,"nil or table expected");
 		}
 		public LuaValue call(LuaValue table, LuaValue metatable) {
 			final LuaValue mt0 = table.checktable().getmetatable();
@@ -465,10 +465,12 @@ public class BaseLib extends TwoArgFunction implements ResourceFinder {
 			this.func = func;
 		}
 		public int read() throws IOException {
-			if ( remaining <= 0 ) {
+			if ( remaining < 0 )
 				return -1;
 			if ( remaining == 0 ) {
 				LuaValue s = func.call();
 				if ( s.isnil() )
-					return -1;
+					return remaining = -1;
 				LuaString ls = s.strvalue();
 				bytes = ls.m_bytes;
 				offset = ls.m_offset;
@@ -477,7 +479,7 @@ public class BaseLib extends TwoArgFunction implements ResourceFinder {
 					return -1;
 			}
 			--remaining;
-			return bytes[offset++];
+			return 0xFF&bytes[offset++];
 		}
 	}
 }
--- a/src/core/org/luaj/vm2/lib/Bit32Lib.java
+++ b/src/core/org/luaj/vm2/lib/Bit32Lib.java
@@ -71,7 +71,7 @@ public class Bit32Lib extends TwoArgFunction {
 			"arshift", "lrotate", "lshift", "rrotate", "rshift"
 		});
 		env.set("bit32", t);
-		env.get("package").get("loaded").set("bit32", t);
+		if (!env.get("package").isnil()) env.get("package").get("loaded").set("bit32", t);
 		return t;
 	}
--- a/src/core/org/luaj/vm2/lib/CoroutineLib.java
+++ b/src/core/org/luaj/vm2/lib/CoroutineLib.java
@@ -82,7 +82,7 @@ public class CoroutineLib extends TwoArgFunction {
 		coroutine.set("yield", new yield());
 		coroutine.set("wrap", new wrap());
 		env.set("coroutine", coroutine);
-		env.get("package").get("loaded").set("coroutine", coroutine);
+		if (!env.get("package").isnil()) env.get("package").get("loaded").set("coroutine", coroutine);
 		return coroutine;
 	}
@@ -92,7 +92,7 @@ public class CoroutineLib extends TwoArgFunction {
 		}
 	}
-	final class resume extends VarArgFunction {
+	static final class resume extends VarArgFunction {
 		public Varargs invoke(Varargs args) {
 			final LuaThread t = args.checkthread(1);
 			return t.resume( args.subargs(2) );
@@ -127,7 +127,7 @@ public class CoroutineLib extends TwoArgFunction {
 		}
 	}
-	final class wrapper extends VarArgFunction {
+	static final class wrapper extends VarArgFunction {
 		final LuaThread luathread;
 		wrapper(LuaThread luathread) {
 			this.luathread = luathread;
--- a/src/core/org/luaj/vm2/lib/DebugLib.java
+++ b/src/core/org/luaj/vm2/lib/DebugLib.java
@@ -84,27 +84,27 @@ public class DebugLib extends TwoArgFunction {
 		try { TRACE = (null != System.getProperty("TRACE")); } catch (Exception e) {}
 	}
-	private static final LuaString LUA             = valueOf("Lua");  
+	static final LuaString LUA             = valueOf("Lua");
 	private static final LuaString QMARK           = valueOf("?");
 	private static final LuaString CALL            = valueOf("call");
 	private static final LuaString LINE            = valueOf("line");
 	private static final LuaString COUNT           = valueOf("count");
 	private static final LuaString RETURN          = valueOf("return");
-	private static final LuaString FUNC            = valueOf("func");  
+	static final LuaString FUNC            = valueOf("func");
-	private static final LuaString ISTAILCALL      = valueOf("istailcall");  
+	static final LuaString ISTAILCALL      = valueOf("istailcall");
-	private static final LuaString ISVARARG        = valueOf("isvararg");  
+	static final LuaString ISVARARG        = valueOf("isvararg");
-	private static final LuaString NUPS            = valueOf("nups");  
+	static final LuaString NUPS            = valueOf("nups");
-	private static final LuaString NPARAMS         = valueOf("nparams");  
+	static final LuaString NPARAMS         = valueOf("nparams");
-	private static final LuaString NAME            = valueOf("name");  
+	static final LuaString NAME            = valueOf("name");
-	private static final LuaString NAMEWHAT        = valueOf("namewhat");  
+	static final LuaString NAMEWHAT        = valueOf("namewhat");
-	private static final LuaString WHAT            = valueOf("what");  
+	static final LuaString WHAT            = valueOf("what");
-	private static final LuaString SOURCE          = valueOf("source");  
+	static final LuaString SOURCE          = valueOf("source");
-	private static final LuaString SHORT_SRC       = valueOf("short_src");  
+	static final LuaString SHORT_SRC       = valueOf("short_src");
-	private static final LuaString LINEDEFINED     = valueOf("linedefined");  
+	static final LuaString LINEDEFINED     = valueOf("linedefined");
-	private static final LuaString LASTLINEDEFINED = valueOf("lastlinedefined");  
+	static final LuaString LASTLINEDEFINED = valueOf("lastlinedefined");
-	private static final LuaString CURRENTLINE     = valueOf("currentline");  
+	static final LuaString CURRENTLINE     = valueOf("currentline");
-	private static final LuaString ACTIVELINES     = valueOf("activelines");  
+	static final LuaString ACTIVELINES     = valueOf("activelines");
 	Globals globals;
@@ -135,7 +135,7 @@ public class DebugLib extends TwoArgFunction {
 		debug.set("upvalueid", new upvalueid());
 		debug.set("upvaluejoin", new upvaluejoin());
 		env.set("debug", debug);
-		env.get("package").get("loaded").set("debug", debug);
+		if (!env.get("package").isnil()) env.get("package").get("loaded").set("debug", debug);
 		return debug;
 	}
@@ -234,7 +234,7 @@ public class DebugLib extends TwoArgFunction {
 	}
 	//	debug.getmetatable (value)
-	final class getmetatable extends LibFunction {
+	static final class getmetatable extends LibFunction {
 		public LuaValue call(LuaValue v) {
 			LuaValue mt = v.getmetatable();
 			return mt != null? mt: NIL;
@@ -311,7 +311,7 @@ public class DebugLib extends TwoArgFunction {
 	}
 	//	debug.setmetatable (value, table)
-	final class setmetatable extends TwoArgFunction { 
+	static final class setmetatable extends TwoArgFunction {
 		public LuaValue call(LuaValue value, LuaValue table) {
 			LuaValue mt = table.opttable(null);
 			switch ( value.type() ) {
@@ -328,7 +328,7 @@ public class DebugLib extends TwoArgFunction {
 	}
 	//	debug.setupvalue (f, up, value)
-	final class setupvalue extends VarArgFunction { 
+	static final class setupvalue extends VarArgFunction {
 		public Varargs invoke(Varargs args) {
 			LuaValue func = args.checkfunction(1);
 			int up = args.checkint(2);
@@ -346,7 +346,7 @@ public class DebugLib extends TwoArgFunction {
 	}
 	//	debug.setuservalue (udata, value)
-	final class setuservalue extends VarArgFunction { 
+	static final class setuservalue extends VarArgFunction {
 		public Varargs invoke(Varargs args) {
 			Object o = args.checkuserdata(1);
 			LuaValue v = args.checkvalue(2);
@@ -370,7 +370,7 @@ public class DebugLib extends TwoArgFunction {
 	}
 	//	debug.upvalueid (f, n)
-	final class upvalueid extends VarArgFunction { 
+	static final class upvalueid extends VarArgFunction {
 		public Varargs invoke(Varargs args) {
 			LuaValue func = args.checkfunction(1);
 			int up = args.checkint(2);
@@ -385,7 +385,7 @@ public class DebugLib extends TwoArgFunction {
 	}
 	//	debug.upvaluejoin (f1, n1, f2, n2)
-	final class upvaluejoin extends VarArgFunction { 
+	static final class upvaluejoin extends VarArgFunction {
 		public Varargs invoke(Varargs args) {
 			LuaClosure f1 = args.checkclosure(1);
 			int n1 = args.checkint(2);
@@ -442,6 +442,10 @@ public class DebugLib extends TwoArgFunction {
 		return callstack().traceback(level);
 	}
 	public CallFrame getCallFrame(int level) {
 		return callstack().getCallFrame(level);
 	}
 	void callHook(LuaThread.State s, LuaValue type, LuaValue arg) {
 		if (s.inhook || s.hookfunc == null) return;
 		s.inhook = true;
@@ -565,7 +569,11 @@ public class DebugLib extends TwoArgFunction {
 					sb.append( ar.name );
 					sb.append( '\'' );
 				} else {
-					sb.append( "function <"+c.shortsource()+":"+c.linedefined()+">" );
+					sb.append( "function <" );
 					sb.append( c.shortsource() );
 					sb.append( ':' );
 					sb.append( c.linedefined() );
 					sb.append( '>' );
 				}
 			}
 			sb.append("\n\t[Java]: in ?");
@@ -641,7 +649,7 @@ public class DebugLib extends TwoArgFunction {
 	}
-	static class CallFrame {
+	public static class CallFrame {
 		LuaFunction f;
 		int pc;
 		int top;
@@ -673,21 +681,21 @@ public class DebugLib extends TwoArgFunction {
 		}
 		Varargs getLocal(int i) {
 			LuaString name = getlocalname(i);
-			if ( name != null )
+			if ( i >= 1 && i <= stack.length && stack[i-1] != null )
-				return varargsOf( name, stack[i-1] );
+				return varargsOf( name == null ? NIL : name, stack[i-1] );
 			else
 				return NIL;
 		}
 		Varargs setLocal(int i, LuaValue value) {
 			LuaString name = getlocalname(i);
-			if ( name != null ) {
+			if ( i >= 1 && i <= stack.length && stack[i-1] != null ) {
 				stack[i-1] = value;
-				return name;
+				return name == null ? NIL : name;
 			} else {
 				return NIL;
 			}
 		}
-		int currentline() {
+		public int currentline() {
 			if ( !f.isclosure() ) return -1;
 			int[] li = f.checkclosure().p.lineinfo;
 			return li==null || pc<0 || pc>=li.length? -1: li[pc];
@@ -696,7 +704,7 @@ public class DebugLib extends TwoArgFunction {
 			if ( !f.isclosure() ) return f.tojstring();
 			return f.checkclosure().p.shortsource() + ":" + currentline();
 		}
-		private int linedefined() {
+		int linedefined() {
 			return f.isclosure()? f.checkclosure().p.linedefined: -1;
 		}
 		LuaString getlocalname(int index) {
@@ -792,13 +800,13 @@ public class DebugLib extends TwoArgFunction {
 		        LuaString vn = (Lua.GET_OPCODE(i) == Lua.OP_GETTABLE)  /* name of indexed variable */
 	                    ? p.getlocalname(t + 1, pc)
 	                    : (t < p.upvalues.length ? p.upvalues[t].name : QMARK);
-				name = kname(p, k);
+				String jname = kname(p, pc, k);
-				return new NameWhat( name.tojstring(), vn != null && vn.eq_b(ENV)? "global": "field" );
+				return new NameWhat( jname, vn != null && vn.eq_b(ENV)? "global": "field" );
 			}
 			case Lua.OP_GETUPVAL: {
 				int u = Lua.GETARG_B(i); /* upvalue index */
 				name = u < p.upvalues.length ? p.upvalues[u].name : QMARK;
-				return new NameWhat( name.tojstring(), "upvalue" );
+				return name == null ? null : new NameWhat( name.tojstring(), "upvalue" );
 			}
 		    case Lua.OP_LOADK:
 		    case Lua.OP_LOADKX: {
@@ -812,8 +820,8 @@ public class DebugLib extends TwoArgFunction {
 		    }
 			case Lua.OP_SELF: {
 				int k = Lua.GETARG_C(i); /* key index */
-				name = kname(p, k);
+				String jname = kname(p, pc, k);
-				return new NameWhat( name.tojstring(), "method" );
+				return new NameWhat( jname, "method" );
 			}
 			default:
 				break;
@@ -822,11 +830,20 @@ public class DebugLib extends TwoArgFunction {
 		return null; /* no useful name found */
 	}
-	static LuaString kname(Prototype p, int c) {
+	static String kname(Prototype p, int pc, int c) {
-		if (Lua.ISK(c) && p.k[Lua.INDEXK(c)].isstring())
+		if (Lua.ISK(c)) {  /* is 'c' a constant? */
-			return p.k[Lua.INDEXK(c)].strvalue();
+			LuaValue k = p.k[Lua.INDEXK(c)];
-		else
+			if (k.isstring()) {  /* literal constant? */
-			return QMARK;
+				return k.tojstring();  /* it is its own name */
 			} /* else no reasonable name found */
 		} else {  /* 'c' is a register */
 			NameWhat what = getobjname(p, pc, c); /* search for 'c' */
 		    if (what != null && "constant".equals(what.namewhat)) {  /* found a constant name? */
 		      return what.name;  /* 'name' already filled */
 		    }
 		    /* else no reasonable name found */
 		}
 		return "?";  /* no reasonable name found */
 	}
 	/*
@@ -867,6 +884,10 @@ public class DebugLib extends TwoArgFunction {
 	        if (reg == a) setreg = pc;  /* jumped code can change 'a' */
 	        break;
 	      }
 	      case Lua.OP_SETLIST: { // Lua.testAMode(Lua.OP_SETLIST) == false
 	    	if ( ((i>>14)&0x1ff) == 0 ) pc++; // if c == 0 then c stored in next op -> skip
 		break;
 	      }
 	      default:
 	        if (Lua.testAMode(op) && reg == a)  /* any instruction that set A */
 	          setreg = pc;
--- a/src/core/org/luaj/vm2/lib/IoLib.java
+++ b/src/core/org/luaj/vm2/lib/IoLib.java
@@ -95,6 +95,12 @@ public class IoLib extends TwoArgFunction {
 		// return number of bytes read if positive, false if eof, throw IOException on other exception
 		abstract public int read(byte[] bytes, int offset, int length) throws IOException;
 		public boolean eof() throws IOException {
 			try {
 				return peek() < 0;
 			} catch (EOFException e) { return true; }
 		}
 		// delegate method access to file methods table
 		public LuaValue get( LuaValue key ) {
 			return filemethods.get(key);
@@ -112,6 +118,14 @@ public class IoLib extends TwoArgFunction {
 		public String tojstring() {
 			return "file: " + Integer.toHexString(hashCode());
 		}
 		public void finalize() {
 			if (!isclosed()) {
 				try {
 					close();
 				} catch (IOException ignore) {}
 			}
 		}
 	}
 	/** Enumerated value representing stdin */
@@ -256,7 +270,7 @@ public class IoLib extends TwoArgFunction {
 		// return the table
 		env.set("io", t);
-		env.get("package").get("loaded").set("io", t);
+		if (!env.get("package").isnil()) env.get("package").get("loaded").set("io", t);
 		return t;
 	}
@@ -269,8 +283,15 @@ public class IoLib extends TwoArgFunction {
 	static final class IoLibV extends VarArgFunction {
 		private File f;
 		public IoLib iolib;
 		private boolean toclose;
 		private Varargs args;
 		public IoLibV() {
 		}
 		public IoLibV(File f, String name, int opcode, IoLib iolib, boolean toclose, Varargs args) {
 			this(f, name, opcode, iolib);
 			this.toclose = toclose;
 			this.args = args.dealias();
 		}
 		public IoLibV(File f, String name, int opcode, IoLib iolib) {
 			super();
 			this.f = f;
@@ -290,22 +311,26 @@ public class IoLib extends TwoArgFunction {
 				case IO_TYPE:		return iolib._io_type(args.arg1());
 				case IO_POPEN:		return iolib._io_popen(args.checkjstring(1),args.optjstring(2,"r"));
 				case IO_OPEN:		return iolib._io_open(args.checkjstring(1), args.optjstring(2,"r"));
-				case IO_LINES:		return iolib._io_lines(args.isvalue(1)? args.checkjstring(1): null);
+				case IO_LINES:		return iolib._io_lines(args);
 				case IO_READ:		return iolib._io_read(args);
 				case IO_WRITE:		return iolib._io_write(args);
 				case FILE_CLOSE:	return iolib._file_close(args.arg1());
 				case FILE_FLUSH:	return iolib._file_flush(args.arg1());
-				case FILE_SETVBUF:	return iolib._file_setvbuf(args.arg1(),args.checkjstring(2),args.optint(3,1024));
+				case FILE_SETVBUF:	return iolib._file_setvbuf(args.arg1(),args.checkjstring(2),args.optint(3,8192));
-				case FILE_LINES:	return iolib._file_lines(args.arg1());
+				case FILE_LINES:	return iolib._file_lines(args);
 				case FILE_READ:		return iolib._file_read(args.arg1(),args.subargs(2));
 				case FILE_SEEK:		return iolib._file_seek(args.arg1(),args.optjstring(2,"cur"),args.optint(3,0));
 				case FILE_WRITE:	return iolib._file_write(args.arg1(),args.subargs(2));
 				case IO_INDEX:		return iolib._io_index(args.arg(2));
-				case LINES_ITER:	return iolib._lines_iter(f);
+				case LINES_ITER:	return iolib._lines_iter(f, toclose, this.args);
 				}
 			} catch ( IOException ioe ) {
 				if (opcode == LINES_ITER) {
 					String s = ioe.getMessage();
 					error(s != null ? s : ioe.toString());
 				}
 				return errorresult(ioe);
 			}
 			return NONE;
@@ -361,6 +386,7 @@ public class IoLib extends TwoArgFunction {
 	// io.popen(prog, [mode]) -> file
 	public Varargs _io_popen(String prog, String mode) throws IOException {
 		if (!"r".equals(mode) && !"w".equals(mode)) argerror(2, "invalid value: '" + mode + "'; must be one of 'r' or 'w'");
 		return openProgram(prog, mode);
 	}
@@ -369,11 +395,12 @@ public class IoLib extends TwoArgFunction {
 		return rawopenfile(FTYPE_NAMED, filename, mode);
 	}
-	//	io.lines(filename) -> iterator
+	//	io.lines(filename, ...) -> iterator
-	public Varargs _io_lines(String filename) {
+	public Varargs _io_lines(Varargs args) {
-		infile = filename==null? input(): ioopenfile(FTYPE_NAMED, filename,"r");
+		String filename = args.optjstring(1, null);
 		File infile = filename==null? input(): ioopenfile(FTYPE_NAMED, filename,"r");
 		checkopen(infile);
-		return lines(infile);
+		return lines(infile, filename != null, args.subargs(2));
 	}
 	//	io.read(...) -> (...)
@@ -401,13 +428,19 @@ public class IoLib extends TwoArgFunction {
 	// file:setvbuf(mode,[size]) -> void
 	public Varargs _file_setvbuf(LuaValue file, String mode, int size) {
 		if ("no".equals(mode)) {
 		} else if ("full".equals(mode)) {
 		} else if ("line".equals(mode)) {
 		} else {
 			argerror(1, "invalid value: '" + mode + "'; must be one of 'no', 'full' or 'line'");
 		}
 		checkfile(file).setvbuf(mode,size);
 		return LuaValue.TRUE;
 	}
-	// file:lines() -> iterator
+	// file:lines(...) -> iterator
-	public Varargs _file_lines(LuaValue file) {
+	public Varargs _file_lines(Varargs args) {
-		return lines(checkfile(file));
+		return lines(checkfile(args.arg1()), false, args.subargs(2));
 	}
 	//	file:read(...) -> (...)
@@ -417,6 +450,12 @@ public class IoLib extends TwoArgFunction {
 	//  file:seek([whence][,offset]) -> pos | nil,error
 	public Varargs _file_seek(LuaValue file, String whence, int offset) throws IOException {
 		if ("set".equals(whence)) {
 		} else if ("end".equals(whence)) {
 		} else if ("cur".equals(whence)) {
 		} else {
 			argerror(1, "invalid value: '" + whence + "'; must be one of 'set', 'cur' or 'end'");
 		}
 		return valueOf( checkfile(file).seek(whence,offset) );
 	}
@@ -433,8 +472,13 @@ public class IoLib extends TwoArgFunction {
 	}
 	//	lines iterator(s,var) -> var'
-	public Varargs _lines_iter(LuaValue file) throws IOException {
+	public Varargs _lines_iter(LuaValue file, boolean toclose, Varargs args) throws IOException {
-		return freadline(checkfile(file));
+		File f = optfile(file);
 		if ( f == null ) argerror(1, "not a file: " + file);
 		if ( f.isclosed() )	error("file is already closed");
 		Varargs ret = ioread(f, args);
 		if (toclose && ret.isnil(1) && f.eof()) f.close();
 		return ret;
 	}
 	private File output() {
@@ -467,7 +511,7 @@ public class IoLib extends TwoArgFunction {
 		return LuaValue.TRUE;
 	}
-	private static Varargs errorresult(Exception ioe) {
+	static Varargs errorresult(Exception ioe) {
 		String s = ioe.getMessage();
 		return errorresult("io error: "+(s!=null? s: ioe.toString()));
 	}
@@ -476,9 +520,9 @@ public class IoLib extends TwoArgFunction {
 		return varargsOf(NIL, valueOf(errortext));
 	}
-	private Varargs lines(final File f) {
+	private Varargs lines(final File f, boolean toclose, Varargs args) {
 		try {
-			return new IoLibV(f,"lnext",LINES_ITER,this);
+			return new IoLibV(f,"lnext",LINES_ITER,this,toclose,args);
 		} catch ( Exception e ) {
 			return error("lines: "+e);
 		}
@@ -492,6 +536,7 @@ public class IoLib extends TwoArgFunction {
 	private Varargs ioread(File f, Varargs args) throws IOException {
 		int i,n=args.narg();
 		if (n == 0) return freadline(f,false);
 		LuaValue[] v = new LuaValue[n];
 		LuaValue ai,vi;
 		LuaString fmt;
@@ -502,10 +547,11 @@ public class IoLib extends TwoArgFunction {
 					break item;
 				case LuaValue.TSTRING:
 					fmt = ai.checkstring();
-					if ( fmt.m_length == 2 && fmt.m_bytes[fmt.m_offset] == '*' ) {
+					if ( fmt.m_length >= 2 && fmt.m_bytes[fmt.m_offset] == '*' ) {
 						switch ( fmt.m_bytes[fmt.m_offset+1] ) {
 						case 'n': vi = freadnumber(f); break item;
-						case 'l': vi = freadline(f); break item;
+						case 'l': vi = freadline(f,false); break item;
 						case 'L': vi = freadline(f,true); break item;
 						case 'a': vi = freadall(f); break item;
 						}
 					}
@@ -537,6 +583,17 @@ public class IoLib extends TwoArgFunction {
 	}
 	private File rawopenfile(int filetype, String filename, String mode) throws IOException {
 		int len = mode.length();
 		for (int i = 0; i < len; i++) { // [rwa][+]?b*
 			char ch = mode.charAt(i);
 			if (i == 0 && "rwa".indexOf(ch) >= 0) continue;
 			if (i == 1 && ch == '+') continue;
 			if (i >= 1 && ch == 'b') continue;
 			len = -1;
 			break;
 		}
 		if (len <= 0) argerror(2, "invalid mode: '" + mode + "'");
 		switch (filetype) {
 		case FTYPE_STDIN: return wrapStdin();
 		case FTYPE_STDOUT: return wrapStdout();
@@ -544,7 +601,7 @@ public class IoLib extends TwoArgFunction {
 		}
 		boolean isreadmode = mode.startsWith("r");
 		boolean isappend = mode.startsWith("a");
-		boolean isupdate = mode.indexOf("+") > 0;
+		boolean isupdate = mode.indexOf('+') > 0;
 		boolean isbinary = mode.endsWith("b");
 		return openFile( filename, isreadmode, isappend, isupdate, isbinary );
 	}
@@ -553,26 +610,27 @@ public class IoLib extends TwoArgFunction {
 	// ------------- file reading utilitied ------------------
 	public static LuaValue freadbytes(File f, int count) throws IOException {
 		if (count == 0) return f.eof() ? NIL : EMPTYSTRING;
 		byte[] b = new byte[count];
 		int r;
 		if ( ( r = f.read(b,0,b.length) ) < 0 )
 			return NIL;
 		return LuaString.valueUsing(b, 0, r);
 	}
-	public static LuaValue freaduntil(File f,boolean lineonly) throws IOException {
+	public static LuaValue freaduntil(File f,boolean lineonly,boolean withend) throws IOException {
 		ByteArrayOutputStream baos = new ByteArrayOutputStream();
 		int c;
 		try {
 			if ( lineonly ) {
-				loop: while ( (c = f.read()) > 0 ) { 
+				loop: while ( (c = f.read()) >= 0 ) {
 					switch ( c ) {
-					case '\r': break;
+					case '\r': if (withend) baos.write(c); break;
-					case '\n': break loop;
+					case '\n': if (withend) baos.write(c); break loop;
 					default: baos.write(c); break;
 					}
 				}
 			} else {
-				while ( (c = f.read()) > 0 ) 
+				while ( (c = f.read()) >= 0 )
 					baos.write(c);
 			}
 		} catch ( EOFException e ) {
@@ -582,15 +640,15 @@ public class IoLib extends TwoArgFunction {
 			(LuaValue) NIL:
 			(LuaValue) LuaString.valueUsing(baos.toByteArray());
 	}
-	public static LuaValue freadline(File f) throws IOException {
+	public static LuaValue freadline(File f,boolean withend) throws IOException {
-		return freaduntil(f,true);
+		return freaduntil(f,true,withend);
 	}
 	public static LuaValue freadall(File f) throws IOException {
 		int n = f.remaining();
 		if ( n >= 0 ) {
-			return freadbytes(f, n);
+			return n == 0 ? EMPTYSTRING : freadbytes(f, n);
 		} else {
-			return freaduntil(f,false);
+			return freaduntil(f,false,false);
 		}
 	}
 	public static LuaValue freadnumber(File f) throws IOException {
--- a/src/core/org/luaj/vm2/lib/LibFunction.java
+++ b/src/core/org/luaj/vm2/lib/LibFunction.java
@@ -139,7 +139,7 @@ abstract public class LibFunction extends LuaFunction {
 	}
 	public String tojstring() {
-		return name != null? name: super.tojstring();
+		return name != null ? "function: " + name : super.tojstring();
 	}
 	/**
@@ -196,7 +196,7 @@ abstract public class LibFunction extends LuaFunction {
 	}
 	public LuaValue call() {
-		return argerror(1,"value");
+		return argerror(1,"value expected");
 	}
 	public LuaValue call(LuaValue a) {
 		return call();
--- a/src/core/org/luaj/vm2/lib/MathLib.java
+++ b/src/core/org/luaj/vm2/lib/MathLib.java
@@ -125,7 +125,7 @@ public class MathLib extends TwoArgFunction {
 		math.set("sqrt", new sqrt());
 		math.set("tan", new tan());
 		env.set("math", math);
-		env.get("package").get("loaded").set("math", math);
+		if (!env.get("package").isnil()) env.get("package").get("loaded").set("math", math);
 		return math;
 	}
@@ -163,10 +163,12 @@ public class MathLib extends TwoArgFunction {
 		}
 	}
-	static final class fmod extends BinaryOp {
+	static final class fmod extends TwoArgFunction {
-		protected double call(double x, double y) {
+		public LuaValue call(LuaValue xv, LuaValue yv) {
-			double q = x/y;
+			if (xv.islong() && yv.islong()) {
-			return x - y * (q>=0? Math.floor(q): Math.ceil(q));
+				return valueOf(xv.tolong() % yv.tolong());
 			}
 			return valueOf(xv.checkdouble() % yv.checkdouble());
 		}
 	}
 	static final class ldexp extends BinaryOp {
@@ -194,27 +196,36 @@ public class MathLib extends TwoArgFunction {
 	static class max extends VarArgFunction {
 		public Varargs invoke(Varargs args) {
-			double m = args.checkdouble(1);
+			LuaValue m = args.checkvalue(1);
-			for ( int i=2,n=args.narg(); i<=n; ++i )
+			for ( int i=2,n=args.narg(); i<=n; ++i ) {
-				m = Math.max(m,args.checkdouble(i));
+				LuaValue v = args.checkvalue(i);
-			return valueOf(m);
+				if (m.lt_b(v)) m = v;
 			}
 			return m;
 		}
 	}
 	static class min extends VarArgFunction {
 		public Varargs invoke(Varargs args) {
-			double m = args.checkdouble(1);
+			LuaValue m = args.checkvalue(1);
-			for ( int i=2,n=args.narg(); i<=n; ++i )
+			for ( int i=2,n=args.narg(); i<=n; ++i ) {
-				m = Math.min(m,args.checkdouble(i));
+				LuaValue v = args.checkvalue(i);
-			return valueOf(m);
+				if (v.lt_b(m)) m = v;
 			}
 			return m;
 		}
 	}
 	static class modf extends VarArgFunction {
 		public Varargs invoke(Varargs args) {
-			double x = args.checkdouble(1);
+			LuaValue n = args.arg1();
 			/* number is its own integer part, no fractional part */
 			if (n.islong()) return varargsOf(n, valueOf(0.0));
 			double x = n.checkdouble();
 			/* integer part (rounds toward zero) */
 			double intPart = ( x > 0 ) ? Math.floor( x ) : Math.ceil( x );
-			double fracPart = x - intPart;
+			/* fractional part (test needed for inf/-inf) */
 			double fracPart = x == intPart ? 0.0 : x - intPart;
 			return varargsOf( valueOf(intPart), valueOf(fracPart) );
 		}
 	}
--- a/src/core/org/luaj/vm2/lib/OsLib.java
+++ b/src/core/org/luaj/vm2/lib/OsLib.java
@@ -80,8 +80,8 @@ import org.luaj.vm2.Varargs;
 * @see <a href="http://www.lua.org/manual/5.1/manual.html#5.8">http://www.lua.org/manual/5.1/manual.html#5.8</a>
 */
 public class OsLib extends TwoArgFunction {
-	public static String TMP_PREFIX    = ".luaj";
+	public static final String TMP_PREFIX    = ".luaj";
-	public static String TMP_SUFFIX    = "tmp";
+	public static final String TMP_SUFFIX    = "tmp";
 	private static final int CLOCK     = 0;
 	private static final int DATE      = 1;
@@ -132,7 +132,7 @@ public class OsLib extends TwoArgFunction {
 		for (int i = 0; i < NAMES.length; ++i)
 			os.set(NAMES[i], new OsLibFunc(i, NAMES[i]));
 		env.set("os", os);
-		env.get("package").get("loaded").set("os", os);
+		if (!env.get("package").isnil()) env.get("package").get("loaded").set("os", os);
 		return os;
 	}
--- a/src/core/org/luaj/vm2/lib/PackageLib.java
+++ b/src/core/org/luaj/vm2/lib/PackageLib.java
@@ -81,23 +81,26 @@ public class PackageLib extends TwoArgFunction {
 	/** The default value to use for package.path.  This can be set with the system property
 	 * <code>"luaj.package.path"</code>, and is <code>"?.lua"</code> by default. */
-	public static String DEFAULT_LUA_PATH;
+	public static final String DEFAULT_LUA_PATH;
 	static {
 		String path = null;
 		try {
-			DEFAULT_LUA_PATH = System.getProperty("luaj.package.path");
+			path = System.getProperty("luaj.package.path");
 		} catch (Exception e) {
 			System.out.println(e.toString());
 		}
-		if (DEFAULT_LUA_PATH == null)
+		if (path == null) {
-			DEFAULT_LUA_PATH = "?.lua";
+			path = "?.lua";
 		}
 		DEFAULT_LUA_PATH = path;
 	}
-	private static final LuaString _LOADED      = valueOf("loaded");
+	static final LuaString _LOADED      = valueOf("loaded");
 	private static final LuaString _LOADLIB     = valueOf("loadlib");
-	private static final LuaString _PRELOAD     = valueOf("preload");
+	static final LuaString _PRELOAD     = valueOf("preload");
-	private static final LuaString _PATH        = valueOf("path");
+	static final LuaString _PATH        = valueOf("path");
-	private static final LuaString _SEARCHPATH  = valueOf("searchpath");
+	static final LuaString _SEARCHPATH  = valueOf("searchpath");
-	private static final LuaString _SEARCHERS   = valueOf("searchers");
+	static final LuaString _SEARCHERS   = valueOf("searchers");
 	/** The globals that were used to load this library. */
 	Globals globals;
@@ -141,6 +144,7 @@ public class PackageLib extends TwoArgFunction {
 		searchers.set(2, lua_searcher     = new lua_searcher());
 		searchers.set(3, java_searcher    = new java_searcher());
 		package_.set(_SEARCHERS, searchers);
 		package_.set("config", FILE_SEP + "\n;\n?\n!\n-\n");
 		package_.get(_LOADED).set("package", package_);
 		env.set("package", package_);
 		globals.package_ = this;
@@ -233,7 +237,7 @@ public class PackageLib extends TwoArgFunction {
 	}
 	public static class loadlib extends VarArgFunction {
-		public Varargs loadlib( Varargs args ) {
+		public Varargs invoke( Varargs args ) {
 			args.checkstring(1);
 			return varargsOf(NIL, valueOf("dynamic libraries not enabled"), valueOf("absent"));
 		}
@@ -252,7 +256,6 @@ public class PackageLib extends TwoArgFunction {
 	public class lua_searcher extends VarArgFunction {
 		public Varargs invoke(Varargs args) {
 			LuaString name = args.checkstring(1);
 			InputStream is = null;
 			// get package path
 			LuaValue path = package_.get(_PATH);
--- a/src/core/org/luaj/vm2/lib/StringLib.java
+++ b/src/core/org/luaj/vm2/lib/StringLib.java
@@ -24,8 +24,8 @@ package org.luaj.vm2.lib;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import org.luaj.vm2.LuaClosure;
 import org.luaj.vm2.Buffer;
 import org.luaj.vm2.LuaClosure;
 import org.luaj.vm2.LuaString;
 import org.luaj.vm2.LuaTable;
 import org.luaj.vm2.LuaValue;
@@ -49,7 +49,7 @@ import org.luaj.vm2.compiler.DumpState;
 * Globals globals = new Globals();
 * globals.load(new JseBaseLib());
 * globals.load(new PackageLib());
- * globals.load(new StringLib());
+ * globals.load(new JseStringLib());
 * System.out.println( globals.get("string").get("upper").call( LuaValue.valueOf("abcde") ) );
 * } </pre>
 * <p>
@@ -83,8 +83,8 @@ public class StringLib extends TwoArgFunction {
 	 */
 	public LuaValue call(LuaValue modname, LuaValue env) {
 		LuaTable string = new LuaTable();
-		string.set("byte", new byte_());
+		string.set("byte", new _byte());
-		string.set("char", new char_());
+		string.set("char", new _char());
 		string.set("dump", new dump());
 		string.set("find", new find());
 		string.set("format", new format());
@@ -97,12 +97,12 @@ public class StringLib extends TwoArgFunction {
 		string.set("reverse", new reverse());
 		string.set("sub", new sub());
 		string.set("upper", new upper());
-		LuaTable mt = LuaValue.tableOf(
+		
 				new LuaValue[] { INDEX, string });
 		env.set("string", string);
-		env.get("package").get("loaded").set("string", string);
+		if (!env.get("package").isnil()) env.get("package").get("loaded").set("string", string);
-		if (LuaString.s_metatable == null)
+		if (LuaString.s_metatable == null) {
-			LuaString.s_metatable = mt;
+			LuaString.s_metatable = LuaValue.tableOf(new LuaValue[] { INDEX, string });
 		}
 		return string;
 	}
@@ -117,7 +117,7 @@ public class StringLib extends TwoArgFunction {
 	 * 
 	 * @param args the calling args
 	 */
-	static final class byte_ extends VarArgFunction {
+	static final class _byte extends VarArgFunction {
 		public Varargs invoke(Varargs args) {
 			LuaString s = args.checkstring(1);
 			int l = s.m_length;
@@ -148,13 +148,13 @@ public class StringLib extends TwoArgFunction {
 	 * 
 	 * @param args the calling VM
 	 */
-	static final class char_ extends VarArgFunction {
+	static final class _char extends VarArgFunction {
 		public Varargs invoke(Varargs args) {
 			int n = args.narg();
 			byte[] bytes = new byte[n];
 			for ( int i=0, a=1; i<n; i++, a++ ) {
 				int c = args.checkint(a);
-				if (c<0 || c>=256) argerror(a, "invalid value");
+				if (c<0 || c>=256) argerror(a, "invalid value for string.char [0; 255]: " + c);
 				bytes[i] = (byte) c;
 			}
 			return LuaString.valueUsing( bytes );
@@ -162,20 +162,22 @@ public class StringLib extends TwoArgFunction {
 	}
 	/**
-	 * string.dump (function)
+	 * string.dump (function[, stripDebug])
 	 * 
 	 * Returns a string containing a binary representation of the given function,
 	 * so that a later loadstring on this string returns a copy of the function.
 	 * function must be a Lua function without upvalues.
 	 * Boolean param stripDebug - true to strip debugging info, false otherwise.
 	 * The default value for stripDebug is true.
 	 * 
 	 * TODO: port dumping code as optional add-on
 	 */
-	static final class dump extends OneArgFunction {
+	static final class dump extends VarArgFunction {
-		public LuaValue call(LuaValue arg) {
+		public Varargs invoke(Varargs args) {
-			LuaValue f = arg.checkfunction();
+			LuaValue f = args.checkfunction(1);
 			ByteArrayOutputStream baos = new ByteArrayOutputStream();
 			try {
-				DumpState.dump( ((LuaClosure)f).p, baos, true );
+				DumpState.dump( ((LuaClosure)f).p, baos, args.optboolean(2, true) );
 				return LuaString.valueUsing(baos.toByteArray());
 			} catch (IOException e) {
 				return error( e.getMessage() );
@@ -228,7 +230,7 @@ public class StringLib extends TwoArgFunction {
 	 * This function does not accept string values containing embedded zeros,
 	 * except as arguments to the q option.
 	 */
-	static final class format extends VarArgFunction {
+	final class format extends VarArgFunction {
 		public Varargs invoke(Varargs args) {
 			LuaString fmt = args.checkstring( 1 );
 			final int n = fmt.length();
@@ -259,7 +261,7 @@ public class StringLib extends TwoArgFunction {
 								break;
 							case 'i':
 							case 'd':
-								fdsc.format( result, args.checkint( arg ) );
+								fdsc.format( result, args.checklong( arg ) );
 								break;
 							case 'o':
 							case 'u':
@@ -298,7 +300,7 @@ public class StringLib extends TwoArgFunction {
 		}
 	}
-	private static void addquoted(Buffer buf, LuaString s) {
+	static void addquoted(Buffer buf, LuaString s) {
 		int c;
 		buf.append( (byte) '"' );
 		for ( int i = 0, n = s.length(); i < n; i++ ) {
@@ -328,7 +330,7 @@ public class StringLib extends TwoArgFunction {
 	private static final String FLAGS = "-+ #0";
-	static class FormatDesc {
+	class FormatDesc {
 		private boolean leftAdjust;
 		private boolean zeroPad;
@@ -338,11 +340,13 @@ public class StringLib extends TwoArgFunction {
 		private static final int MAX_FLAGS = 5;
 		private int width;
-		private int precision;
+		int precision;
 		public final int conversion;
 		public final int length;
 		public final String src;
 		public FormatDesc(Varargs args, LuaString strfrmt, final int start) {
 			int p = start, n = strfrmt.length();
 			int c = 0;
@@ -390,6 +394,7 @@ public class StringLib extends TwoArgFunction {
 			zeroPad &= !leftAdjust; // '-' overrides '0'
 			conversion = c;
 			length = p - start;
 			src = strfrmt.substring(start - 1, p).tojstring();
 		}
 		public void format(Buffer buf, byte c) {
@@ -465,8 +470,7 @@ public class StringLib extends TwoArgFunction {
 		}
 		public void format(Buffer buf, double x) {
-			// TODO
+			buf.append( StringLib.this.format(src, x) );
 			buf.append( String.valueOf( x ) );
 		}
 		public void format(Buffer buf, LuaString s) {
@@ -476,13 +480,17 @@ public class StringLib extends TwoArgFunction {
 			buf.append(s);
 		}
-		public static final void pad(Buffer buf, char c, int n) {
+		public final void pad(Buffer buf, char c, int n) {
 			byte b = (byte)c;
 			while ( n-- > 0 )
 				buf.append(b);
 		}
 	}
 	protected String format(String src, double x) {
 		return String.valueOf(x);
 	}
 	/**
 	 * string.gmatch (s, pattern)
 	 * 
@@ -519,18 +527,20 @@ public class StringLib extends TwoArgFunction {
 		private final int srclen;
 		private final MatchState ms;
 		private int soffset;
 		private int lastmatch;
 		public GMatchAux(Varargs args, LuaString src, LuaString pat) {
 			this.srclen = src.length();
 			this.ms = new MatchState(args, src, pat);
 			this.soffset = 0;
 			this.lastmatch = -1;
 		}
 		public Varargs invoke(Varargs args) {
-			for ( ; soffset<srclen; soffset++ ) {
+			for ( ; soffset<=srclen; soffset++ ) {
 				ms.reset();
 				int res = ms.match(soffset, 0);
-				if ( res >=0 ) {
+				if ( res >=0 && res != lastmatch ) {
 					int soff = soffset;
-					soffset = res;
+					lastmatch = soffset = res;
 					return ms.push_captures( true, soff, res );
 				}
 			}
@@ -589,6 +599,7 @@ public class StringLib extends TwoArgFunction {
 			LuaString src = args.checkstring( 1 );
 			final int srclen = src.length();
 			LuaString p = args.checkstring( 2 );
 			int lastmatch = -1; /* end of last match */
 			LuaValue repl = args.arg( 3 );
 			int max_s = args.optint( 4, srclen + 1 );
 			final boolean anchor = p.length() > 0 && p.charAt( 0 ) == '^';
@@ -601,18 +612,15 @@ public class StringLib extends TwoArgFunction {
 			while ( n < max_s ) {
 				ms.reset();
 				int res = ms.match( soffset, anchor ? 1 : 0 );
-				if ( res != -1 ) {
+				if ( res != -1 && res != lastmatch ) {  /* match? */
 					n++;
-					ms.add_value( lbuf, soffset, res, repl );
+					ms.add_value( lbuf, soffset, res, repl );  /* add replacement to buffer */
 					soffset = lastmatch = res;
 				}
-				if ( res != -1 && res > soffset )
+				else if ( soffset < srclen ) /* otherwise, skip one character */
 					soffset = res;
 				else if ( soffset < srclen )
 					lbuf.append( (byte) src.luaByte( soffset++ ) );
-				else
+				else break;   /* end of subject */
-					break;
+				if ( anchor ) break;
 				if ( anchor )
 					break;
 			}
 			lbuf.append( src.substring( soffset, srclen ) );
 			return varargsOf(lbuf.tostring(), valueOf(n));
@@ -764,7 +772,7 @@ public class StringLib extends TwoArgFunction {
 			boolean anchor = false;
 			int poff = 0;
-			if ( pat.luaByte( 0 ) == '^' ) {
+			if ( pat.length() > 0 && pat.luaByte( 0 ) == '^' ) {
 				anchor = true;
 				poff = 1;
 			}
@@ -785,7 +793,7 @@ public class StringLib extends TwoArgFunction {
 		return NIL;
 	}
-	private static int posrelat( int pos, int len ) {
+	static int posrelat( int pos, int len ) {
 		return ( pos >= 0 ) ? pos : len + pos + 1;
 	}
@@ -795,6 +803,8 @@ public class StringLib extends TwoArgFunction {
 	private static final LuaString SPECIALS = valueOf("^$*+?.([%-");
 	private static final int MAX_CAPTURES = 32;
 	private static final int MAXCCALLS = 200;
 	private static final int CAP_UNFINISHED = -1;
 	private static final int CAP_POSITION = -2;
@@ -807,12 +817,12 @@ public class StringLib extends TwoArgFunction {
 	private static final byte MASK_CONTROL		= 0x40;
 	private static final byte MASK_HEXDIGIT		= (byte)0x80;
-	private static final byte[] CHAR_TABLE;
+	static final byte[] CHAR_TABLE;
 	static {
 		CHAR_TABLE = new byte[256];
-		for ( int i = 0; i < 256; ++i ) {
+		for ( int i = 0; i < 128; ++i ) {
 			final char c = (char) i;
 			CHAR_TABLE[i] = (byte)( ( Character.isDigit( c ) ? MASK_DIGIT : 0 ) |
 							( Character.isLowerCase( c ) ? MASK_LOWERCASE : 0 ) |
@@ -821,7 +831,7 @@ public class StringLib extends TwoArgFunction {
 			if ( ( c >= 'a' && c <= 'f' ) || ( c >= 'A' && c <= 'F' ) || ( c >= '0' && c <= '9' ) ) {
 				CHAR_TABLE[i] |= MASK_HEXDIGIT;
 			}
-			if ( ( c >= '!' && c <= '/' ) || ( c >= ':' && c <= '@' ) ) {
+			if ( ( c >= '!' && c <= '/' ) || ( c >= ':' && c <= '@' ) || ( c >= '[' && c <= '`' ) || ( c >= '{' && c <= '~' ) ) {
 				CHAR_TABLE[i] |= MASK_PUNCT;
 			}
 			if ( ( CHAR_TABLE[i] & ( MASK_LOWERCASE | MASK_UPPERCASE ) ) != 0 ) {
@@ -833,11 +843,12 @@ public class StringLib extends TwoArgFunction {
 		CHAR_TABLE['\r'] |= MASK_SPACE;
 		CHAR_TABLE['\n'] |= MASK_SPACE;
 		CHAR_TABLE['\t'] |= MASK_SPACE;
-		CHAR_TABLE[0x0C /* '\v' */ ] |= MASK_SPACE;
+		CHAR_TABLE[0x0B /* '\v' */ ] |= MASK_SPACE;
 		CHAR_TABLE['\f'] |= MASK_SPACE;
 	};
 	static class MatchState {
 		int matchdepth;  /* control for recursive depth (to avoid C stack overflow) */
 		final LuaString s;
 		final LuaString p;
 		final Varargs args;
@@ -852,10 +863,12 @@ public class StringLib extends TwoArgFunction {
 			this.level = 0;
 			this.cinit = new int[ MAX_CAPTURES ];
 			this.clen = new int[ MAX_CAPTURES ];
 			this.matchdepth = MAXCCALLS;
 		}
 		void reset() {
 			level = 0;
 			this.matchdepth = MAXCCALLS;
 		}
 		private void add_s( Buffer lbuf, LuaString news, int soff, int e ) {
@@ -866,8 +879,14 @@ public class StringLib extends TwoArgFunction {
 					lbuf.append( (byte) b );
 				} else {
 					++i; // skip ESC
-					b = (byte) news.luaByte( i );
+					b = (byte)(i < l ? news.luaByte( i ) : 0);
 					if ( !Character.isDigit( (char) b ) ) {
 						if (b != L_ESC) error( "invalid use of '" + (char)L_ESC +
 							"' in replacement string: after '" + (char)L_ESC +
 							"' must be '0'-'9' or '" + (char)L_ESC +
 							"', but found " + (i < l ? "symbol '" + (char)b + "' with code " + b +
 							" at pos " + (i + 1) :
 							"end of string"));
 						lbuf.append( b );
 					} else if ( b == '0' ) {
 						lbuf.append( s.substring( soff, e ) );
@@ -924,7 +943,7 @@ public class StringLib extends TwoArgFunction {
 				if ( i == 0 ) {
 					return s.substring( soff, end );
 				} else {
-					return error( "invalid capture index" );
+					return error( "invalid capture index %" + (i + 1) );
 				}
 			} else {
 				int l = clen[i];
@@ -943,7 +962,7 @@ public class StringLib extends TwoArgFunction {
 		private int check_capture( int l ) {
 			l -= '1';
 			if ( l < 0 || l >= level || this.clen[l] == CAP_UNFINISHED ) {
-				error("invalid capture index");
+				error("invalid capture index %" + (l + 1));
 			}
 			return l;
 		}
@@ -961,19 +980,19 @@ public class StringLib extends TwoArgFunction {
 			switch ( p.luaByte( poffset++ ) ) {
 			case L_ESC:
 				if ( poffset == p.length() ) {
-					error( "malformed pattern (ends with %)" );
+					error( "malformed pattern (ends with '%')" );
 				}
 				return poffset + 1;
 			case '[':
-				if ( p.luaByte( poffset ) == '^' ) poffset++;
+				if ( poffset != p.length() && p.luaByte( poffset ) == '^' ) poffset++;
 				do {
 					if ( poffset == p.length() ) {
-						error( "malformed pattern (missing ])" );
+						error( "malformed pattern (missing ']')" );
 					}
-					if ( p.luaByte( poffset++ ) == L_ESC && poffset != p.length() )
+					if ( p.luaByte( poffset++ ) == L_ESC && poffset < p.length() )
-						poffset++;
+						poffset++; /* skip escapes (e.g. '%]') */
-				} while ( p.luaByte( poffset ) != ']' );
+				} while ( poffset == p.length() || p.luaByte( poffset ) != ']' );
 				return poffset + 1;
 			default:
 				return poffset;
@@ -993,9 +1012,10 @@ public class StringLib extends TwoArgFunction {
 			case 'c': res = ( cdata & MASK_CONTROL ) != 0; break;
 			case 'p': res = ( cdata & MASK_PUNCT ) != 0; break;
 			case 's': res = ( cdata & MASK_SPACE ) != 0; break;
 			case 'g': res = ( cdata & ( MASK_ALPHA | MASK_DIGIT | MASK_PUNCT ) ) != 0; break;
 			case 'w': res = ( cdata & ( MASK_ALPHA | MASK_DIGIT ) ) != 0; break;
 			case 'x': res = ( cdata & MASK_HEXDIGIT ) != 0; break;
-			case 'z': res = ( c == 0 ); break;
+			case 'z': res = ( c == 0 ); break;  /* deprecated option */
 			default: return cl == c;
 			}
 			return ( lcl == cl ) ? res : !res;
@@ -1037,6 +1057,8 @@ public class StringLib extends TwoArgFunction {
 		 * where match ends, otherwise returns -1.
 		 */
 		int match( int soffset, int poffset ) {
 			if (matchdepth-- == 0) error("pattern too complex");
 			try {
 				while ( true ) {
 					// Check if we are at the end of the pattern -
 					// equivalent to the '\0' case in the C version, but our pattern
@@ -1062,13 +1084,14 @@ public class StringLib extends TwoArgFunction {
 							continue;
 						case 'f': {
 							poffset += 2;
-						if ( p.luaByte( poffset ) != '[' ) {
+							if ( poffset == p.length() || p.luaByte( poffset ) != '[' ) {
-							error("Missing [ after %f in pattern");
+								error("missing '[' after '%f' in pattern");
 							}
 							int ep = classend( poffset );
-						int previous = ( soffset == 0 ) ? -1 : s.luaByte( soffset - 1 );
+							int previous = ( soffset == 0 ) ? '\0' : s.luaByte( soffset - 1 );
 							int next = ( soffset == s.length() ) ? '\0' : s.luaByte( soffset );
 							if ( matchbracketclass( previous, poffset, ep - 1 ) ||
-							 matchbracketclass( s.luaByte( soffset ), poffset, ep - 1 ) )
+								 !matchbracketclass( next, poffset, ep - 1 ) )
 								return -1;
 							poffset = ep;
 							continue;
@@ -1112,6 +1135,9 @@ public class StringLib extends TwoArgFunction {
 						continue;
 					}
 				}
 			} finally {
 				matchdepth++;
 			}
 		}
 		int max_expand( int soff, int poff, int ep ) {
@@ -1175,7 +1201,7 @@ public class StringLib extends TwoArgFunction {
 		int matchbalance( int soff, int poff ) {
 			final int plen = p.length();
 			if ( poff == plen || poff + 1 == plen ) {
-				error( "unbalanced pattern" );
+				error( "malformed pattern (missing arguments to '%b')" );
 			}
 			final int slen = s.length();
 			if ( soff >= slen )
--- a/src/core/org/luaj/vm2/lib/TableLib.java
+++ b/src/core/org/luaj/vm2/lib/TableLib.java
@@ -70,16 +70,10 @@ public class TableLib extends TwoArgFunction {
 		table.set("sort", new sort());
 		table.set("unpack", new unpack());
 		env.set("table", table);
-		env.get("package").get("loaded").set("table", table);
+		if (!env.get("package").isnil()) env.get("package").get("loaded").set("table", table);
 		return NIL;
 	}
 	static class TableLibFunction extends LibFunction {
 		public LuaValue call() {
 			return argerror(1, "table expected, got no value");
 		}
 	}
 	// "concat" (table [, sep [, i [, j]]]) -> string
 	static class concat extends TableLibFunction {
 		public LuaValue call(LuaValue list) {
@@ -100,18 +94,22 @@ public class TableLib extends TwoArgFunction {
 	static class insert extends VarArgFunction {
 		public Varargs invoke(Varargs args) {
 			switch (args.narg()) {
 			case 0: case 1: {
 				return argerror(2, "value expected");
 			}
 			case 2: {
-				LuaTable table = args.arg1().checktable();
+				LuaTable table = args.checktable(1);
 				table.insert(table.length()+1,args.arg(2));
 				return NONE;
 			}
-			default: {
+			case 3: {
-				args.arg1().checktable().insert(args.checkint(2),args.arg(3));
+				LuaTable table = args.checktable(1);
 				int pos = args.checkint(2);
 				int max = table.length() + 1;
 				if (pos < 1 || pos > max) argerror(2, "position out of bounds: " + pos + " not between 1 and " + max);
 				table.insert(pos, args.arg(3));
 				return NONE;
 			}
 			default: {
 				return error("wrong number of arguments to 'table.insert': " + args.narg() + " (must be 2 or 3)");
 			}
 			}
 		}
 	}
@@ -128,15 +126,21 @@ public class TableLib extends TwoArgFunction {
 	// "remove" (table [, pos]) -> removed-ele
 	static class remove extends VarArgFunction {
 		public Varargs invoke(Varargs args) {
-			return args.arg1().checktable().remove(args.optint(2, 0));
+			LuaTable table = args.checktable(1);
 			int size = table.length();
 			int pos = args.optint(2, size);
 			if (pos != size && (pos < 1 || pos > size + 1)) {
 				argerror(2, "position out of bounds: " + pos + " not between 1 and " + (size + 1));
 			}
 			return table.remove(pos);
 		}
 	}
 	// "sort" (table [, comp])
 	static class sort extends VarArgFunction {
 		public Varargs invoke(Varargs args) {
-			args.arg1().checktable().sort(
+			args.checktable(1).sort(
-					args.arg(2).isnil()? NIL: args.arg(2).checkfunction());
+					args.isnil(2)? NIL: args.checkfunction(2));
 			return NONE;
 		}
 	}
@@ -146,11 +150,9 @@ public class TableLib extends TwoArgFunction {
 	static class unpack extends VarArgFunction {
 		public Varargs invoke(Varargs args) {
 			LuaTable t = args.checktable(1);
-			switch (args.narg()) {
+			// do not waste resource for calc rawlen if arg3 is not nil
-			case 1: return t.unpack();
+			int len = args.arg(3).isnil() ? t.length() : 0;
-			case 2: return t.unpack(args.checkint(2));
+			return t.unpack(args.optint(2, 1), args.optint(3, len));
 			default: return t.unpack(args.checkint(2), args.checkint(3));
 			}
 		}
 	}
 }
--- a/src/core/org/luaj/vm2/lib/TableLibFunction.java
+++ b/src/core/org/luaj/vm2/lib/TableLibFunction.java
@@ -0,0 +1,9 @@
 package org.luaj.vm2.lib;
 import org.luaj.vm2.LuaValue;
 class TableLibFunction extends LibFunction {
 	public LuaValue call() {
 		return argerror(1, "table expected, got no value");
 	}
 }
--- a/src/jse/org/luaj/vm2/ast/Visitor.java
+++ b/src/jse/org/luaj/vm2/ast/Visitor.java
@@ -101,7 +101,7 @@ abstract public class Visitor {
 		visitExps(args.exps);
 	}
 	public void visit(TableField field) {
-		if ( field.name != null );
+		if ( field.name != null )
 			visit( field.name );
 		if ( field.index != null )
 			field.index.accept(this);
--- a/src/jse/org/luaj/vm2/lib/jse/CoerceJavaToLua.java
+++ b/src/jse/org/luaj/vm2/lib/jse/CoerceJavaToLua.java
@@ -21,6 +21,7 @@
 ******************************************************************************/
 package org.luaj.vm2.lib.jse;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
@@ -133,7 +134,7 @@ public class CoerceJavaToLua {
 	}
-	static final Map COERCIONS = new HashMap();
+	static final Map COERCIONS = Collections.synchronizedMap(new HashMap());
 	static {
 		Coercion boolCoercion = new BoolCoercion() ;
--- a/src/jse/org/luaj/vm2/lib/jse/JavaMethod.java
+++ b/src/jse/org/luaj/vm2/lib/jse/JavaMethod.java
@@ -114,8 +114,19 @@ class JavaMethod extends JavaMember {
 		final JavaMethod[] methods;
 		// no parammeter method index in overload method
 		int noArgMethodIndex = -1;
 		Overload(JavaMethod[] methods) {
 			this.methods = methods;
 			JavaMethod m;
 			for (int i=0; i<methods.length; i++) {
 				m = methods[i];
 				if (m.fixedargs.length == 0 && m.varargs == null) {
 					noArgMethodIndex = i;
 					break;
 				}
 			}
 		}
 		public LuaValue call() {
@@ -140,6 +151,10 @@ class JavaMethod extends JavaMember {
 		private LuaValue invokeBestMethod(Object instance, Varargs args) {
 			JavaMethod best = null;
 			int n = args.narg();
 			if (n == 0 && noArgMethodIndex != -1) {
 				best = methods[noArgMethodIndex];
 			} else {
 				int score = CoerceLuaToJava.SCORE_UNCOERCIBLE;
 				for ( int i=0; i<methods.length; i++ ) {
 					int s = methods[i].score(args);
@@ -150,6 +165,7 @@ class JavaMethod extends JavaMember {
 							break;
 					}
 				}
 			}
 			// any match? 
 			if ( best == null )
--- a/src/jse/org/luaj/vm2/lib/jse/JseBaseLib.java
+++ b/src/jse/org/luaj/vm2/lib/jse/JseBaseLib.java
@@ -21,6 +21,7 @@
 ******************************************************************************/
 package org.luaj.vm2.lib.jse;
 import java.io.BufferedInputStream;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.IOException;
@@ -106,9 +107,10 @@ public class JseBaseLib extends org.luaj.vm2.lib.BaseLib {
 		if ( ! f.exists() )
 			return super.findResource(filename);
 		try {
-			return new FileInputStream(f);
+			return new BufferedInputStream(new FileInputStream(f));
 		} catch ( IOException ioe ) {
 			return null;
 		}
 	}
 }
--- a/src/jse/org/luaj/vm2/lib/jse/JseIoLib.java
+++ b/src/jse/org/luaj/vm2/lib/jse/JseIoLib.java
@@ -133,7 +133,7 @@ public class JseIoLib extends IoLib {
 			this( null, null, o );
 		}
 		public String tojstring() {
-			return "file ("+this.hashCode()+")";
+			return "file (" + (this.closed ? "closed" : String.valueOf(this.hashCode())) + ")";
 		}
 		public boolean isstdfile() {
 			return file == null;
@@ -321,7 +321,7 @@ public class JseIoLib extends IoLib {
 		}
 		public int remaining() throws IOException {
-			return 0;
+			return -1;
 		}
 		public int peek() throws IOException, EOFException {
--- a/src/jse/org/luaj/vm2/lib/jse/JseMathLib.java
+++ b/src/jse/org/luaj/vm2/lib/jse/JseMathLib.java
@@ -24,6 +24,7 @@ package org.luaj.vm2.lib.jse;
 import org.luaj.vm2.Globals;
 import org.luaj.vm2.LuaValue;
 import org.luaj.vm2.lib.LibFunction;
 import org.luaj.vm2.lib.TwoArgFunction;
 /** 
 * Subclass of {@link LibFunction} which implements the lua standard {@code math} 
@@ -76,8 +77,9 @@ public class JseMathLib extends org.luaj.vm2.lib.MathLib {
 		LuaValue math = env.get("math");
 		math.set("acos", new acos());
 		math.set("asin", new asin());
-		math.set("atan", new atan());
+		LuaValue atan =  new atan2();
-		math.set("atan2", new atan2());
+		math.set("atan", atan);
 		math.set("atan2", atan);
 		math.set("cosh", new cosh());
 		math.set("exp", new exp());
 		math.set("log", new log());
@@ -89,11 +91,21 @@ public class JseMathLib extends org.luaj.vm2.lib.MathLib {
 	static final class acos extends UnaryOp { protected double call(double d) { return Math.acos(d); } }
 	static final class asin extends UnaryOp { protected double call(double d) { return Math.asin(d); } }
-	static final class atan extends UnaryOp { protected double call(double d) { return Math.atan(d); } }
+	static final class atan2 extends TwoArgFunction { 
-	static final class atan2 extends BinaryOp { protected double call(double y, double x) { return Math.atan2(y, x); } }
+		public LuaValue call(LuaValue x, LuaValue y) {
 			return valueOf(Math.atan2(x.checkdouble(), y.optdouble(1)));
 		} 
 	}
 	static final class cosh extends UnaryOp { protected double call(double d) { return Math.cosh(d); } }
 	static final class exp extends UnaryOp { protected double call(double d) { return Math.exp(d); } }
-	static final class log extends UnaryOp { protected double call(double d) { return Math.log(d); } }
+	static final class log extends TwoArgFunction {
 		public LuaValue call(LuaValue x, LuaValue base) {
 			double nat = Math.log(x.checkdouble());
 			double b = base.optdouble(Math.E);
 			if (b != Math.E) nat /= Math.log(b);
 			return valueOf(nat);
 		}
 	}
 	static final class pow extends BinaryOp { protected double call(double x, double y) { return Math.pow(x, y); } }
 	static final class sinh extends UnaryOp { protected double call(double d) { return Math.sinh(d); } }
 	static final class tanh extends UnaryOp { protected double call(double d) { return Math.tanh(d); } }
@@ -105,3 +117,4 @@ public class JseMathLib extends org.luaj.vm2.lib.MathLib {
 }
--- a/src/jse/org/luaj/vm2/lib/jse/JseOsLib.java
+++ b/src/jse/org/luaj/vm2/lib/jse/JseOsLib.java
@@ -74,13 +74,13 @@ import org.luaj.vm2.lib.OsLib;
 public class JseOsLib extends org.luaj.vm2.lib.OsLib {
 	/** return code indicating the execute() threw an I/O exception */
-	public static int EXEC_IOEXCEPTION =  1;
+	public static final int EXEC_IOEXCEPTION =  1;
 	/** return code indicating the execute() was interrupted */
-	public static int EXEC_INTERRUPTED = -2;
+	public static final int EXEC_INTERRUPTED = -2;
 	/** return code indicating the execute() threw an unknown exception */
-	public static int EXEC_ERROR       = -3;
+	public static final int EXEC_ERROR       = -3;
 	/** public constructor */
 	public JseOsLib() {
@@ -120,13 +120,13 @@ public class JseOsLib extends org.luaj.vm2.lib.OsLib {
 		if ( ! f.exists() )
 			throw new IOException("No such file or directory");
 		if ( ! f.renameTo(new File(newname)) )
-			throw new IOException("Failed to delete");
+			throw new IOException("Failed to rename");
 	}
 	protected String tmpname() {
 		try {
 			java.io.File f = java.io.File.createTempFile(TMP_PREFIX ,TMP_SUFFIX);
-			return f.getName();
+			return f.getAbsolutePath();
 		} catch ( IOException ioe ) {
 			return super.tmpname();
 		}
--- a/src/jse/org/luaj/vm2/lib/jse/JsePlatform.java
+++ b/src/jse/org/luaj/vm2/lib/jse/JsePlatform.java
@@ -23,8 +23,8 @@ package org.luaj.vm2.lib.jse;
 import org.luaj.vm2.Globals;
 import org.luaj.vm2.LoadState;
 import org.luaj.vm2.LuaThread;
 import org.luaj.vm2.LuaValue;
 import org.luaj.vm2.Varargs;
 import org.luaj.vm2.compiler.LuaC;
 import org.luaj.vm2.lib.Bit32Lib;
 import org.luaj.vm2.lib.CoroutineLib;
@@ -97,7 +97,7 @@ public class JsePlatform {
 		globals.load(new PackageLib());
 		globals.load(new Bit32Lib());
 		globals.load(new TableLib());
-		globals.load(new StringLib());
+		globals.load(new JseStringLib());
 		globals.load(new CoroutineLib());
 		globals.load(new JseMathLib());
 		globals.load(new JseIoLib());
@@ -124,10 +124,11 @@ public class JsePlatform {
 	/** Simple wrapper for invoking a lua function with command line arguments.
-	 * The supplied function is first given a new Globals object, 
+	 * The supplied function is first given a new Globals object as its environment
 	 * then the program is run with arguments.
 	 * @return {@link Varargs} containing any values returned by mainChunk.
 	 */
-	public static void luaMain(LuaValue mainChunk, String[] args) {
+	public static Varargs luaMain(LuaValue mainChunk, String[] args) {
 		Globals g = standardGlobals();
 		int n = args.length;
 		LuaValue[] vargs = new LuaValue[args.length];
@@ -137,6 +138,6 @@ public class JsePlatform {
 		arg.set("n", n);
 		g.set("arg", arg);
 		mainChunk.initupvalue1(g);
-		mainChunk.invoke(LuaValue.varargsOf(vargs));
+		return mainChunk.invoke(LuaValue.varargsOf(vargs));
 	}
 }
--- a/src/jse/org/luaj/vm2/lib/jse/JseStringLib.java
+++ b/src/jse/org/luaj/vm2/lib/jse/JseStringLib.java
@@ -0,0 +1,39 @@
 /*******************************************************************************
 * Copyright (c) 2009 Luaj.org. All rights reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 ******************************************************************************/
 package org.luaj.vm2.lib.jse;
 public class JseStringLib extends org.luaj.vm2.lib.StringLib {
 	/** public constructor */
 	public JseStringLib() {
 	}
 	protected String format(String src, double x) {
 		String out;
 		try {
 			out = String.format(src, new Object[] {Double.valueOf(x)});
 		} catch (Throwable e) {
 			out = super.format(src, x);
 		}
 		return out;
 	}
 }
--- a/src/jse/org/luaj/vm2/lib/jse/LuajavaLib.java
+++ b/src/jse/org/luaj/vm2/lib/jse/LuajavaLib.java
@@ -112,7 +112,7 @@ public class LuajavaLib extends VarArgFunction {
 				LuaTable t = new LuaTable();
 				bind( t, this.getClass(), NAMES, BINDCLASS );
 				env.set("luajava", t);
-				env.get("package").get("loaded").set("luajava", t);
+				if (!env.get("package").isnil()) env.get("package").get("loaded").set("luajava", t);
 				return t;
 			}
 			case BINDCLASS: {
--- a/test/junit/org/luaj/vm2/AllTests.java
+++ b/test/junit/org/luaj/vm2/AllTests.java
@@ -32,6 +32,7 @@ import org.luaj.vm2.compiler.DumpLoadEndianIntTest;
 import org.luaj.vm2.compiler.LuaParserTests;
 import org.luaj.vm2.compiler.RegressionTests;
 import org.luaj.vm2.compiler.SimpleTests;
 import org.luaj.vm2.lib.jse.JsePlatformTest;
 import org.luaj.vm2.lib.jse.LuaJavaCoercionTest;
 import org.luaj.vm2.lib.jse.LuajavaAccessibleMembersTest;
 import org.luaj.vm2.lib.jse.LuajavaClassMembersTest;
@@ -85,6 +86,7 @@ public class AllTests {
 		// library tests
 		TestSuite lib = new TestSuite("Library Tests");
 		lib.addTestSuite(JsePlatformTest.class);
 		lib.addTestSuite(LuajavaAccessibleMembersTest.class);
 		lib.addTestSuite(LuajavaClassMembersTest.class);
 		lib.addTestSuite(LuaJavaCoercionTest.class);
--- a/test/junit/org/luaj/vm2/lib/jse/JsePlatformTest.java
+++ b/test/junit/org/luaj/vm2/lib/jse/JsePlatformTest.java
@@ -0,0 +1,21 @@
 package org.luaj.vm2.lib.jse;
 import junit.framework.TestCase;
 import org.luaj.vm2.Globals;
 import org.luaj.vm2.LuaValue;
 import org.luaj.vm2.Varargs;
 public class JsePlatformTest extends TestCase {
 	public void testLuaMainPassesArguments() {
 		Globals globals = JsePlatform.standardGlobals();   
 		LuaValue chunk = globals.load("return #arg, arg.n, arg[2], arg[1]");
 		Varargs results = JsePlatform.luaMain(chunk, new String[] { "aaa", "bbb" });
 		assertEquals(results.narg(), 4);
 		assertEquals(results.arg(1), LuaValue.valueOf(2));
 		assertEquals(results.arg(2), LuaValue.valueOf(2));
 		assertEquals(results.arg(3), LuaValue.valueOf("bbb"));
 		assertEquals(results.arg(4), LuaValue.valueOf("aaa"));
 	}
 }
--- a/version.properties
+++ b/version.properties
@@ -1 +1 @@
-version: 3.0.1
+version: 3.0.2