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| .. | ||
| luaj_xowa.jar | ||
| readme.txt | ||
NOTE: This page is also in XOWA under home/wiki/Help:Luaj
== Source ==
The luaj_xowa.jar was built using the source at http://sourceforge.net/projects/luaj/files/luaj-3.0/3.0-beta2/luaj-3.0-beta2.zip/download.
Its source is not currently included with XOWA. It is available at the following location: https://sourceforge.net/projects/xowa/files/support/luaj/
== Modification ==
The luaj_xowa.jar was created for the following reasons:
* Backward compatibility:
: Scribunto is currently using Lua 5.1 whereas luaj 3.0 is designed for Lua 5.2
: Lua 5.2 is not backward-compatible with Lua 5.1; several functions are obsoleted (for example, table.maxn)
: The luaj_xowa.jar was tailored to support Scribunto's 5.1 environment.
* Patches / bug fixes:
: Luaj has a handful of minor issues / defects. They are listed below.
== $engines variable ==
Note that the $engines variable refers to /xowa/bin/any/lua/mediawiki/extensions/Scribunto/engines/
== Luaj changes ==
=== Luaj 2.0.3 errors fixed in 3.0 ===
==== os.time doesn't handle dates before 1970 ====
* fix : incorrect Birth / Date; EX: ru.w:Пушкин,_Александр_Сергеевич
* file: /src/core/org/luaj/vm2/lib/OsLib.java
==== pairs.next fails when setting val to null ====
* fix : Finnish declension table; EX:d:Latvia
* file: /src/core/org/luaj/vm2/LuaTable.java
=== Luaj 2.0.3 features removed from 3.0 ===
==== string.gfind deprecated ====
* fix : missing Video_game_reviews; EX: w:Sonic_Heroes
* file: /src/core/org/luaj/vm2/lib/StringLib.java
* code: call
<pre>
old:
"sub"} );
new:
"sub", "gfind"} );
</pre>
* code: invoke
<pre>
add:
case 4:
case 9: return StringLib.gmatch( args );
</pre>
==== math.log10 deprecated ====
* fix : blank references; EX:w:Earth
* file: /src/jse/org/luaj/vm2/lib/JseMathLib.java
* code:
<pre>
math.set("log10", new log10());
static final class log10 extends UnaryOp { protected double call(double d) { return Math.log10(d); } }
</pre>
==== math.mod deprecated ====
* fix : missing table; EX:d:աղբիւր
* file: /src/core/org/luaj/vm2/lib/MathLib.java
* code:
<pre>
fmod fmod_func = new fmod();
math.set("mod", fmod_func);
math.set("fmod", fmod_func);
</pre>
==== table.maxn deprecated ====
file: /src/core/org/luaj/vm2/lib/TableLib.java
* code:
<pre>
public LuaValue getn() {
int len = length();
for (int n = len; n > 0; --n )
if ( !rawget(n).isnil() )
return LuaInteger.valueOf(n);
return ZERO;
}
</pre>
file: /src/core/org/luaj/vm2/lib/TableLib.java
<pre>
table.set("maxn", new maxn());
static class maxn extends OneArgFunction {
public LuaValue call(LuaValue arg) {
return LuaValue.valueOf(arg.checktable().maxn());
}
}
</pre>
==== table.getn deprecated ====
* fix : missing text; EX: d:aceite d:Module:pt-verb-form-of
* file: /src/core/org/luaj/vm2/LuaTable.java
code:
<pre>
public LuaValue getn() {
int len = length();
for (int n = len; n > 0; --n )
if ( !rawget(n).isnil() )
return LuaInteger.valueOf(n);
return ZERO;
}
</pre>
* file: /src/core/org/luaj/vm2/lib/TableLib.java
* code:
<pre>
table.set("getn", new getn());
static class getn extends OneArgFunction {
public LuaValue call(LuaValue arg) {
return arg.checktable().getn();
}
}
</pre>
==== automatic arg variable in varargs function deprecated ====
* fix : Horizontal timeline; EX: w:Cretaceous%E2%80%93Paleogene_extinction_event
* file: /src/core/org/luaj/vm2/LuaClosure.java
code:
<pre>
case Lua.OP_GETTABUP: /* A B C R(A) := UpValue[B][RK(C)] */
// stack[a] = upValues[i>>>23].getValue().get((c=(i>>14)&0x1ff)>0xff? k[c&0x0ff]: stack[c]);
// HACK: handle deprecated "arg" for "..."
int OP_GETTABUP_c = (i>>14)&0x1ff;
boolean OP_GETTABUP_b = OP_GETTABUP_c>0xff;
LuaValue OP_GETTABUP_idx = OP_GETTABUP_b ? k[OP_GETTABUP_c&0x0ff]: stack[OP_GETTABUP_c];
stack[a] = upValues[i>>>23].getValue().get(OP_GETTABUP_idx);
// HACK: handle deprecated "arg"
if ( p.is_vararg == 1
&& stack[a] == NIL
&& OP_GETTABUP_b
&& "arg".equals(OP_GETTABUP_idx.tojstring())
)
stack[a] = new LuaTable(varargs);
continue;
</pre>
=== Luaj 3.0 defects ===
==== os.date does not accept UTC format ====
* fix : incorrect age in ym; EX:w:Supreme_Court_of_the_United_States
* file: /src/core/org/luaj/vm2/lib/OsLib.java
* proc: invoke.DATE
<pre>
boolean utc = false;
if (s.startsWith("!")) {
utc = true;
s = s.substring(1);
}
if (s.equals("*t")) {
Calendar d = Calendar.getInstance();
long time_in_ms = (long)(t*1000);
if (utc) {
java.util.TimeZone current_tz = d.getTimeZone();
int offset_from_utc = current_tz.getOffset(time_in_ms);
time_in_ms += -offset_from_utc;
}
</pre>
==== string.gsub fails with out_of_bounds error ====
* fix : blank references; EX:w:Earth
* file: /src/core/org/luaj/vm2/lib/StringLib.java
* proc: gsub
<pre>
old:
if ( anchor )
break;
new:
if ( anchor )
break;
if (soffset >= srclen) break; // assert soffset is in bounds, else will throw ArrayIndexOutOfBounds exception;
</pre>
==== string.gsub fails if string is empty====
* fix : blank references; EX:w:Woburn,_Massachusetts
* file: /src/core/org/luaj/vm2/lib/StringLib.java
* proc: gsub
<pre>
static Varargs gsub( Varargs args ) {
LuaString src = args.checkstring( 1 );
final int srclen = src.length();
if (srclen == 0) return varargsOf(src, LuaValue.ZERO); // exit early
</pre>
==== string.format ignores precision for double args ====
* fix : Convert calls will show full precision for numbers; EX:w:Tomato
* file: /src/core/org/luaj/vm2/lib/StringLib.java
<pre>
old:
case 'G':
fdsc.format( result, args.checkdouble( arg ) );
new:
case 'c': // merged c with e E f F g G
fdsc.format( result, fmt.tojstring().substring(i - fdsc.length, i), args.checkdouble( arg ));
</pre>
* proc: format
<pre>
old:
buf.append( v) );
new:
try {
fmtstr = "%" + fmtstr; // % stripped above
buf.append( String.format(fmtstr, v) ); // call String.format
}catch (java.util.MissingFormatWidthException e) {
// HACK: handle invalid format of "%0.1f" -> "%.1f"; %0 should be followed by valid number, but in this case, ignore it;
String old_fmt = e.getFormatSpecifier();
if (old_fmt.startsWith("0")) {
String new_fmt = old_fmt.substring(1); // remove initial 0
fmtstr = fmtstr.replace(old_fmt, new_fmt);
buf.append( String.format(fmtstr, v) ); // call String.format
}
else
throw e;
}
</pre>
* note: forces a 1.5 JRE (as opposed to 1.3)
==== string.tonumber should trim all whitespace ====
* fix: Population tables; EX: w:Woburn,_Massachusetts
* file: /src/core/org/luaj/vm2/LuaString.java
* proc: scannumber
<pre>
// trim ws
int idx = i;
while (idx < j) {
switch (m_bytes[idx]) {
case 9: case 10: case 13: case 32:
++idx;
i = idx;
break;
default:
idx = j;
break;
}
}
idx = j - 1;
while (idx >= i) {
switch (m_bytes[idx]) {
case 9: case 10: case 13: case 32:
j = idx;
--idx;
break;
default:
idx = i -1;
break;
}
}
</pre>
==== multi-byte strings not fully supported ====
* fix : Thai calendar; EX:th.w:เหตุการณ์ปัจจุบัน
* file: /src/core/org/luaj/vm2/LuaString.java
<pre style='overflow:auto'>
public static LuaString valueOf(char[] chars, int off, int len) {
// COMMENTED: does not handle 2+ byte chars; assumes 1 char = 1 byte
// byte[] b = new byte[len];
// for ( int i=0; i<len; i++ )
// b[i] = (byte) chars[i + off];
// return valueOf(b, 0, len);
int bry_len = 0;
for (int i = 0; i < len; i++) // iterate over chars to sum all single / multi-byte chars
bry_len += LuaString.Utf8_len_by_int((int)(chars[i + off]));
byte[] bry = new byte[bry_len];
int bry_idx = 0;
for (int i = 0; i < len; i++) {
int c = (int)(chars[i + off]);
int c_len_in_bytes = LuaString.Utf8_encode_by_int(c, bry, bry_idx);
bry_idx += c_len_in_bytes;
}
return valueOf(bry, 0, bry_len);
}
public static String decodeAsUtf8(byte[] bytes, int offset, int length) {
// COMMENTED: does not handle 3+ byte chars
// int i,j,n,b;
// for ( i=offset,j=offset+length,n=0; i<j; ++n ) {
// switch ( 0xE0 & bytes[i++] ) {
// case 0xE0: ++i;
// case 0xC0: ++i;
// }
// }
// char[] chars=new char[n];
// for ( i=offset,j=offset+length,n=0; i<j; ) {
// chars[n++] = (char) (
// ((b=bytes[i++])>=0||i>=j)? b:
// (b<-32||i+1>=j)? (((b&0x3f) << 6) | (bytes[i++]&0x3f)):
// (((b&0xf) << 12) | ((bytes[i++]&0x3f)<<6) | (bytes[i++]&0x3f)));
// }
// return new String(chars);
return new String(bytes, offset, length, java.nio.charset.Charset.forName("UTF-8"));
}
public static int lengthAsUtf8(char[] chars) {
// COMMENTED: does not handle 3+ byte chars
// int i,b;
// char c;
// for ( i=b=chars.length; --i>=0; )
// if ( (c=chars[i]) >=0x80 )
// b += (c>=0x800)? 2: 1;
// return b;
int len = chars.length;
int rv = 0;
for (int i = 0; i < len; i++)
rv += LuaString.Utf8_len_by_int(chars[i]);
return rv;
}
public static int encodeToUtf8(char[] chars, int nchars, byte[] bytes, int off) {
// COMMENTED: does not handle 4+ byte chars; already using Encode_by_int, so might as well be consistent
// char c;
// int j = off;
// for ( int i=0; i<nchars; i++ ) {
// if ( (c = chars[i]) < 0x80 ) {
// bytes[j++] = (byte) c;
// } else if ( c < 0x800 ) {
// bytes[j++] = (byte) (0xC0 | ((c>>6) & 0x1f));
// bytes[j++] = (byte) (0x80 | ( c & 0x3f));
// } else {
// bytes[j++] = (byte) (0xE0 | ((c>>12) & 0x0f));
// bytes[j++] = (byte) (0x80 | ((c>>6) & 0x3f));
// bytes[j++] = (byte) (0x80 | ( c & 0x3f));
// }
// }
// return j - off;
int bry_idx = off;
for (int i = 0; i < nchars; i++ ) {
int c = chars[i];
int c_len_in_bytes = LuaString.Utf8_encode_by_int(c, bytes, bry_idx);
bry_idx += c_len_in_bytes;
}
return nchars; // NOTE: code returned # of bytes which is wrong; Globals.UTF8Stream.read caches rv as j which is used as index to char[] not byte[]; will throw out of bounds exception if bytes returned
}
public static int Utf8_len_by_int(int charAsInt) {
if (charAsInt < 0x80) return 1;
else if (charAsInt < (1 << 11)) return 2;
else if (charAsInt < (1 << 16)) return 3;
else if (charAsInt < (1 << 21)) return 4;
else if (charAsInt < (1 << 26)) return 5;
else return 6;
}
public static int Utf8_len_by_byte(byte b) {
int i = b & 0xff;
switch (i) {
case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7: case 8: case 9: case 10: case 11: case 12: case 13: case 14: case 15:
case 16: case 17: case 18: case 19: case 20: case 21: case 22: case 23: case 24: case 25: case 26: case 27: case 28: case 29: case 30: case 31:
case 32: case 33: case 34: case 35: case 36: case 37: case 38: case 39: case 40: case 41: case 42: case 43: case 44: case 45: case 46: case 47:
case 48: case 49: case 50: case 51: case 52: case 53: case 54: case 55: case 56: case 57: case 58: case 59: case 60: case 61: case 62: case 63:
case 64: case 65: case 66: case 67: case 68: case 69: case 70: case 71: case 72: case 73: case 74: case 75: case 76: case 77: case 78: case 79:
case 80: case 81: case 82: case 83: case 84: case 85: case 86: case 87: case 88: case 89: case 90: case 91: case 92: case 93: case 94: case 95:
case 96: case 97: case 98: case 99: case 100: case 101: case 102: case 103: case 104: case 105: case 106: case 107: case 108: case 109: case 110: case 111:
case 112: case 113: case 114: case 115: case 116: case 117: case 118: case 119: case 120: case 121: case 122: case 123: case 124: case 125: case 126: case 127:
case 128: case 129: case 130: case 131: case 132: case 133: case 134: case 135: case 136: case 137: case 138: case 139: case 140: case 141: case 142: case 143:
case 144: case 145: case 146: case 147: case 148: case 149: case 150: case 151: case 152: case 153: case 154: case 155: case 156: case 157: case 158: case 159:
case 160: case 161: case 162: case 163: case 164: case 165: case 166: case 167: case 168: case 169: case 170: case 171: case 172: case 173: case 174: case 175:
case 176: case 177: case 178: case 179: case 180: case 181: case 182: case 183: case 184: case 185: case 186: case 187: case 188: case 189: case 190: case 191:
return 1;
case 192: case 193: case 194: case 195: case 196: case 197: case 198: case 199: case 200: case 201: case 202: case 203: case 204: case 205: case 206: case 207:
case 208: case 209: case 210: case 211: case 212: case 213: case 214: case 215: case 216: case 217: case 218: case 219: case 220: case 221: case 222: case 223:
return 2;
case 224: case 225: case 226: case 227: case 228: case 229: case 230: case 231: case 232: case 233: case 234: case 235: case 236: case 237: case 238: case 239:
return 3;
case 240: case 241: case 242: case 243: case 244: case 245: case 246: case 247:
return 4;
case 248: case 249: case 250: case 251:
return 5;
case 252: case 253:
return 6;
case 254: case 255:
default:
return 6;
}
}
public static int Utf8_decode_to_int(byte[] ary, int pos) {
byte b0 = ary[pos];
if ((b0 & 0x80) == 0) {
return b0;
}
else if ((b0 & 0xE0) == 0xC0) {
return ( b0 & 0x1f) << 6
| ( ary[pos + 1] & 0x3f)
;
}
else if ((b0 & 0xF0) == 0xE0) {
return ( b0 & 0x0f) << 12
| ((ary[pos + 1] & 0x3f) << 6)
| ( ary[pos + 2] & 0x3f)
;
}
else if ((b0 & 0xF8) == 0xF0) {
return ( b0 & 0x07) << 18
| ((ary[pos + 1] & 0x3f) << 12)
| ((ary[pos + 2] & 0x3f) << 6)
| ( ary[pos + 3] & 0x3f)
;
}
else if ((b0 & 0xFC) == 0xF8) {
return ( b0 & 0x03) << 24
| ((ary[pos + 1] & 0x3f) << 18)
| ((ary[pos + 2] & 0x3f) << 12)
| ((ary[pos + 3] & 0x3f) << 6)
| ( ary[pos + 4] & 0x3f)
;
}
else if ((b0 & 0xFC) == 0xFC) {
return ( b0 & 0x03) << 30
| ((ary[pos + 1] & 0x3f) << 24)
| ((ary[pos + 2] & 0x3f) << 18)
| ((ary[pos + 3] & 0x3f) << 12)
| ((ary[pos + 4] & 0x3f) << 6)
| ( ary[pos + 5] & 0x3f)
;
}
else {
return b0 & 0xFF;
}
}
public static int Utf8_encode_by_int(int charAsInt, byte[] src, int pos) {
if (charAsInt < 0x80) {
src[pos] = (byte)charAsInt;
return 1;
}
else if (charAsInt < (1 << 11)) {
src[pos] = (byte)(0xC0 | (charAsInt >> 6));
src[++pos] = (byte)(0x80 | (charAsInt & 0x3F));
return 2;
}
else if (charAsInt < (1 << 16)) {
src[pos] = (byte)(0xE0 | (charAsInt >> 12));
src[++pos] = (byte)(0x80 | (charAsInt >> 6) & 0x3F);
src[++pos] = (byte)(0x80 | (charAsInt & 0x3F));
return 3;
}
else if (charAsInt < (1 << 21)) {
src[pos] = (byte)(0xF0 | (charAsInt >> 18));
src[++pos] = (byte)(0x80 | (charAsInt >> 12) & 0x3F);
src[++pos] = (byte)(0x80 | (charAsInt >> 6) & 0x3F);
src[++pos] = (byte)(0x80 | (charAsInt & 0x3F));
return 4;
}
else if (charAsInt < (1 << 26)) {
src[pos] = (byte)(0xF8 | (charAsInt >> 24));
src[++pos] = (byte)(0x80 | (charAsInt >> 18) & 0x3F);
src[++pos] = (byte)(0x80 | (charAsInt >> 12) & 0x3F);
src[++pos] = (byte)(0x80 | (charAsInt >> 6) & 0x3F);
src[++pos] = (byte)(0x80 | (charAsInt & 0x3F));
return 5;
}
else if (charAsInt < (1 << 31)) {
src[pos] = (byte)(0xFC | (charAsInt >> 30));
src[++pos] = (byte)(0x80 | (charAsInt >> 24) & 0x3F);
src[++pos] = (byte)(0x80 | (charAsInt >> 18) & 0x3F);
src[++pos] = (byte)(0x80 | (charAsInt >> 12) & 0x3F);
src[++pos] = (byte)(0x80 | (charAsInt >> 6) & 0x3F);
src[++pos] = (byte)(0x80 | (charAsInt & 0x3F));
return 6;
}
else if (charAsInt == 0) {
src[pos] = (byte)0xC0;
src[++pos] = (byte)0x80;
return -1;
}
return -1;
}
</pre>
* file: /src/core/org/luaj/vm2/compiler/LexState.java
* proc: read_string
<pre style='overflow:auto'>
if (c > UCHAR_MAX)
lexerror("escape sequence too large", TK_STRING);
save(c, false); // NOTE: specify that c is integer and does not need conversion; EX: \128 -> 128 -> (char)128, not Utf8_encode(128)
</pre>
* file: /src/core/org/luaj/vm2/compiler/LexState.java
<pre style='overflow:auto'>
void save(int c) {save(c, true);}
void save(int c, boolean c_might_be_utf8) {
int bytes_len = c_might_be_utf8 ? LuaString.Utf8_len_by_byte((byte)c) : 1;
if (bytes_len > 1) { // c is 1st byte of utf8 multi-byte sequence; read required number of bytes and convert to char; EX: ← is serialized in z as 226,134,144; c is currently 226; read 134 and 144 and convert to ←
temp_bry[0] = (byte)c;
for (int i = 1; i < bytes_len; i++) {
nextChar();
temp_bry[i] = (byte)current;
}
c = LuaString.Utf8_decode_to_int(temp_bry, 0);
}
if ( buff == null || nbuff + 1 > buff.length )
buff = LuaC.realloc( buff, nbuff*2+1 );
buff[nbuff++] = (char)c;
}
private static byte[] temp_bry = new byte[6];
</pre>
=== build.xml ===
* note: this change is needed to get luaj to compile with the String.format(String, double) call
* file: build.xml
<pre>
old:
<javac destdir="build/jme/classes" encoding="utf-8" source="1.3" target="1.2" bootclasspathref="wtk-libs"
srcdir="build/jme/src"/>
<javac destdir="build/jse/classes" encoding="utf-8" source="1.3" target="1.3"
classpath="lib/bcel-5.2.jar"
srcdir="build/jse/src"
excludes="**/script/*,**/Lua2Java*,lua*"/>
<javac destdir="build/jse/classes" encoding="utf-8" source="1.5" target="1.5"
classpath="build/jse/classes"
srcdir="build/jse/src"
includes="**/script/*,**/Lua2Java*"/>
<javac destdir="build/jse/classes" encoding="utf-8" source="1.3" target="1.3"
classpath="build/jse/classes"
srcdir="build/jse/src"
includes="lua*"/>
new:
<javac destdir="build/jse/classes" encoding="utf-8" source="1.5" target="1.5"
classpath="lib/bcel-5.2.jar"
srcdir="build/jse/src"
excludes="**/script/*,**/Lua2Java*,lua*"/>
<javac destdir="build/jse/classes" encoding="utf-8" source="1.5" target="1.5"
classpath="build/jse/classes"
srcdir="build/jse/src"
includes="**/script/*,**/Lua2Java*"/>
<javac destdir="build/jse/classes" encoding="utf-8" source="1.5" target="1.5"
classpath="build/jse/classes"
srcdir="build/jse/src"
includes="lua*"/>
</pre>
=== Luaj tests ===
<pre>
package org.luaj.vm2;
import org.luaj.vm2.lib.StringLib;
import junit.framework.*;
public class Xowa_tst extends TestCase {
private Xowa_fxt fxt = new Xowa_fxt();
public void test_tonumber_ws() {
fxt.Test_tonumber_int("123" , 123);
fxt.Test_tonumber_int("\t\n\r 123\t\n\r" , 123);
fxt.Test_tonumber_nil("1a");
fxt.Test_tonumber_nil("1 2");
fxt.Test_tonumber_nil("");
fxt.Test_tonumber_nil("\t\n\r \t\n\r");
}
public void test_gsub() {
fxt.Test_gsub("abc", "a", "A", "Abc"); // basic
fxt.Test_gsub("a#b", "#", "", "ab"); // match() fails when shortening string
fxt.Test_gsub("", "%b<>", "A", ""); // balance() fails with out of index when find is blank
}
public void test_format() {
fxt.Test_format("%.1f" , "1.23", "1.2"); // apply precision; 1 decimal place
fxt.Test_format("(%.1f)", "1.23", "(1.2)"); // handle substring; format_string should be "%.1f" not "(%.1f)"
fxt.Test_format("%0.1f" , "1.23", "1.2"); // handle invalid precision of 0
}
}
class Xowa_fxt {
public void Test_tonumber_int(String raw, int expd) {
LuaString actl_str = LuaString.valueOf(raw);
LuaInteger actl_int = (LuaInteger)actl_str.tonumber();
Assert.assertEquals(expd, actl_int.v);
}
public void Test_tonumber_nil(String raw) {
LuaString actl_str = LuaString.valueOf(raw);
Assert.assertEquals(LuaValue.NIL, actl_str.tonumber());
}
public void Test_gsub(String text, String regx, String repl, String expd) {
Varargs actl_args = StringLib.gsub_test(LuaValue.varargsOf(new LuaValue[] {LuaValue.valueOf(text), LuaValue.valueOf(regx), LuaValue.valueOf(repl)}));
Assert.assertEquals(expd, actl_args.checkstring(1).tojstring());
}
public void Test_format(String fmt, String val, String expd) {
Varargs actl_args = StringLib.format_test(LuaValue.varargsOf(new LuaValue[] {LuaValue.valueOf(fmt), LuaValue.valueOf(val)}));
Assert.assertEquals(expd, actl_args.checkstring(1).tojstring());
}
}
</pre>
== Scribunto related ==
None of these changes affect the luaj_xowa.jar. They are noted for comprehensiveness's sake.
=== getfenv/setfenv deprecated ===
* add lua-compat-env
: source: https://github.com/davidm/lua-compat-env
: target: $engines/LuaCommon/lualib/lua-compat-env .lua
* add alias to $engines/Luaj/mw_main.lua
: _G.getfenv = require 'compat_env'.getfenv
: _G.setfenv = require 'compat_env'.setfenv
* change xowa.jar to load debugLibrary
: Globals.load(new DebugLib());
=== loadString deprecated ===
* add alias to $engines/Luaj/mw_main.lua
: _G.loadstring = load
=== table.unpack deprecated ===
* add alias to $engines/Luaj/mw_main.lua
: _G.unpack = table.unpack