diff --git a/src/main/java/lua/value/LDouble.java b/src/main/java/lua/value/LDouble.java
index 453453d9..be9a26d0 100644
--- a/src/main/java/lua/value/LDouble.java
+++ b/src/main/java/lua/value/LDouble.java
@@ -44,5 +44,36 @@ public class LDouble extends LNumber {
 	public int luaAsInt() {
 		return (int) m_value;
 	}
+
+	// binary compares on integers, first dispatch
+	public boolean luaBinCmpUnknown(int opcode, LValue lhs) {
+		return lhs.luaBinCmpDouble( opcode, this.m_value );
+	}
+	
+	// binary compares on mixtures of doubles and integers
+	public boolean luaBinCmpInteger(int opcode, int rhs) {
+		return luaBinCmpDoubleDouble( opcode, m_value, (double) rhs );
+	}
+	
+	// binary compares on doubles
+	public boolean luaBinCmpDouble(int opcode, double rhs) {
+		return luaBinCmpDoubleDouble( opcode, m_value, rhs );
+	}
+	
+	// compare two doubles
+	public static boolean luaBinCmpDoubleDouble( int opcode, double lhs, double rhs ) {
+		switch ( opcode ) {
+		case Lua.OP_EQ: return lhs == rhs;
+		case Lua.OP_LT: return lhs < rhs;
+		case Lua.OP_LE: return lhs <= rhs;
+		}
+		luaUnsupportedOperation();
+		return false;
+	}
+
+	/** Arithmetic negative */
+	public LValue luaUnaryMinus() {
+		return new LDouble( -m_value );
+	}
 	
 }
diff --git a/src/main/java/lua/value/LInteger.java b/src/main/java/lua/value/LInteger.java
index a71972bc..d88a7e75 100644
--- a/src/main/java/lua/value/LInteger.java
+++ b/src/main/java/lua/value/LInteger.java
@@ -40,4 +40,32 @@ public class LInteger extends LNumber {
 	public LValue luaBinOpDouble(int opcode, double rhs) {
 		return LDouble.luaBinOpDoubleDouble(opcode, (double) m_value, rhs );
 	}
+	
+	// binary compare for integers, first dispatch
+	public boolean luaBinCmpUnknown(int opcode, LValue lhs) {
+		return lhs.luaBinCmpInteger( opcode, this.m_value );
+	}
+	
+	// unsupported except for numbers
+	public boolean luaBinCmpInteger(int opcode, int rhs) {
+		switch ( opcode ) {
+		case Lua.OP_EQ: return m_value == rhs;
+		case Lua.OP_LT: return m_value < rhs;
+		case Lua.OP_LE: return m_value <= rhs;
+		}
+		luaUnsupportedOperation();
+		return false;
+	}
+	
+	// unsupported except for numbers
+	public boolean luaBinCmpDouble(int opcode, double rhs) {
+		return LDouble.luaBinCmpDoubleDouble(opcode, (double) m_value, rhs );
+	}
+
+	/** Arithmetic negative */
+	public LValue luaUnaryMinus() {
+		return new LInteger( -m_value );
+	}
+
+
 }
diff --git a/src/main/java/lua/value/LString.java b/src/main/java/lua/value/LString.java
index 0f0b2dd3..94b0aeb5 100644
--- a/src/main/java/lua/value/LString.java
+++ b/src/main/java/lua/value/LString.java
@@ -18,4 +18,10 @@ public class LString extends LValue {
 	public String luaAsString() {
 		return m_string;
 	}
+
+	/** Built-in opcode LEN, for Strings and Tables */
+	public LValue luaLength() {
+		return new LInteger( m_string.length() );
+	}
+
 }
diff --git a/src/main/java/lua/value/LTable.java b/src/main/java/lua/value/LTable.java
index f2b41457..d2e8ec24 100644
--- a/src/main/java/lua/value/LTable.java
+++ b/src/main/java/lua/value/LTable.java
@@ -26,4 +26,9 @@ public class LTable extends LValue {
 	public String luaAsString() {
 		return m_hash.toString();
 	}
+	
+	/** Built-in opcode LEN, for Strings and Tables */
+	public LValue luaLength() {
+		return new LInteger( m_array.size() );
+	}
 }
diff --git a/src/main/java/lua/value/LValue.java b/src/main/java/lua/value/LValue.java
index a52bd0ad..0b1f33e4 100644
--- a/src/main/java/lua/value/LValue.java
+++ b/src/main/java/lua/value/LValue.java
@@ -34,6 +34,24 @@ public class LValue {
 		return luaUnsupportedOperation();
 	}
 
+	// unsupported except for numbers
+	public boolean luaBinCmpUnknown(int opcode, LValue lhs) {
+		luaUnsupportedOperation();
+		return false;
+	}
+	
+	// unsupported except for numbers
+	public boolean luaBinCmpInteger(int opcode, int rhs) {
+		luaUnsupportedOperation();
+		return false;
+	}
+	
+	// unsupported except for numbers
+	public boolean luaBinCmpDouble(int opcode, double rhs) {
+		luaUnsupportedOperation();
+		return false;
+	}
+	
 	/** set a value in a table
 	 */
 	public void luaSetTable(LValue key, LValue value) {
@@ -61,5 +79,17 @@ public class LValue {
 		luaUnsupportedOperation();
 		return 0;
 	}
+
+	/** Arithmetic negative */
+	public LValue luaUnaryMinus() {
+		return luaUnsupportedOperation();
+	}
+
+	/** Built-in opcode LEN, for Strings and Tables */
+	public LValue luaLength() {
+		// TODO: call meta-method TM_LEN here
+		return luaUnsupportedOperation();
+	}
+
 	
 }
diff --git a/src/test/res/compile.sh b/src/test/res/compile.sh
index 76810893..febb2b50 100644
--- a/src/test/res/compile.sh
+++ b/src/test/res/compile.sh
@@ -1,7 +1,10 @@
 #!/bin/bash
 LUA_HOME=/cygdrive/c/programs/lua5.1
-for x in test1 test2 test3 test4
+TESTS="test1 test2 test3 test4 test5"
+#TESTS="test5"
+for x in $TESTS
 do
     echo compiling $x
 	${LUA_HOME}/luac5.1.exe -l -o ${x}.luac ${x}.lua
+	${LUA_HOME}/lua5.1.exe ${x}.luac
 done
diff --git a/src/test/res/test5.lua b/src/test/res/test5.lua
new file mode 100644
index 00000000..48fae4a3
--- /dev/null
+++ b/src/test/res/test5.lua
@@ -0,0 +1,17 @@
+
+ i = 777
+ while i<780 do
+   print(i)
+   i = i+1
+ end
+
+ a,b = 0,1
+ while true do               -- infinite loop
+   print( b )
+  a,b = b,a+b
+  if a>10 then break end   -- exit the loop if the condition is true
+ end
+
+ for count = 336,330,-2 do print(count) end  -- numerical iteration
+ 
+-- for key,value in pairs({a=10, 3.14159265358, c="banana"}) do print(key, value) end 
\ No newline at end of file
diff --git a/src/test/res/test5.luac b/src/test/res/test5.luac
new file mode 100644
index 00000000..240a9c5c
Binary files /dev/null and b/src/test/res/test5.luac differ