diff --git a/src/core/org/luaj/lib/DebugLib.java b/src/core/org/luaj/lib/DebugLib.java
index fd470f1f..3aa05e4c 100644
--- a/src/core/org/luaj/lib/DebugLib.java
+++ b/src/core/org/luaj/lib/DebugLib.java
@@ -298,23 +298,11 @@ public class DebugLib extends LFunction {
 		return null;
 	}
 
-	private LString getlocalname (LPrototype f, int local_number, int pc) {
-	  int i;
-	  for (i = 0; i<f.locvars.length && f.locvars[i].startpc <= pc; i++) {
-	    if (pc < f.locvars[i].endpc) {  /* is variable active? */
-	      local_number--;
-	      if (local_number == 0)
-	        return f.locvars[i].varname;
-	    }
-	  }
-	  return null;  /* not found */
-	}
-
 	private LString findlocal(LuaState vm, int cc, int n) {
 		CallInfo ci = vm.calls[cc];
 		LString name;
 		LPrototype fp = ci.closure.p;
-		if ( fp!=null && (name = getlocalname(fp, n, ci.pc-1)) != null)
+		if ( fp!=null && (name = fp.getlocalname(n, ci.pc-1)) != null)
 			return name;
 		return null;
 	}
diff --git a/src/core/org/luaj/vm/CallInfo.java b/src/core/org/luaj/vm/CallInfo.java
index 1f15aa42..91907872 100644
--- a/src/core/org/luaj/vm/CallInfo.java
+++ b/src/core/org/luaj/vm/CallInfo.java
@@ -40,4 +40,8 @@ public class CallInfo {
         this.pc = 0;
     }
 
+	public boolean isLua() {
+		return true;
+	}
+
 }
diff --git a/src/core/org/luaj/vm/LClosure.java b/src/core/org/luaj/vm/LClosure.java
index 3390d35e..4d9dc60f 100644
--- a/src/core/org/luaj/vm/LClosure.java
+++ b/src/core/org/luaj/vm/LClosure.java
@@ -59,4 +59,9 @@ public class LClosure extends LFunction {
 		return env;
 	}
 
+	/** Returns true if this is a lua closure, false otherwise */
+	public boolean isClosure() {
+		return true;
+	}
+
 }
diff --git a/src/core/org/luaj/vm/LNumber.java b/src/core/org/luaj/vm/LNumber.java
index 759b0caf..4aa550d1 100644
--- a/src/core/org/luaj/vm/LNumber.java
+++ b/src/core/org/luaj/vm/LNumber.java
@@ -96,5 +96,9 @@ public class LNumber extends LValue {
 	public void luaConcatTo(ByteArrayOutputStream baos) {
 		luaAsString().luaConcatTo( baos );
 	}
-
+	
+	/** Returns true if this is or can be made into a number */
+	public boolean isNumber() {
+		return true;
+	}
 }
diff --git a/src/core/org/luaj/vm/LPrototype.java b/src/core/org/luaj/vm/LPrototype.java
index 2581e996..b86849a2 100644
--- a/src/core/org/luaj/vm/LPrototype.java
+++ b/src/core/org/luaj/vm/LPrototype.java
@@ -52,4 +52,21 @@ public class LPrototype {
 	public int is_vararg;
 	public int maxstacksize;
 
+	/** Get the name of a local variable.
+	 * 
+	 * @param number the local variable number to look up
+	 * @param pc the program counter
+	 * @return the name, or null if not found
+	 */
+	public LString getlocalname(int number, int pc) {
+	  int i;
+	  for (i = 0; i<locvars.length && locvars[i].startpc <= pc; i++) {
+	    if (pc < locvars[i].endpc) {  /* is variable active? */
+	    	number--;
+	      if (number == 0)
+	        return locvars[i].varname;
+	    }
+	  }
+	  return null;  /* not found */
+	}
 }
diff --git a/src/core/org/luaj/vm/LString.java b/src/core/org/luaj/vm/LString.java
index bff8a350..ecc96701 100644
--- a/src/core/org/luaj/vm/LString.java
+++ b/src/core/org/luaj/vm/LString.java
@@ -455,5 +455,11 @@ public class LString extends LValue {
 	public void luaConcatTo(ByteArrayOutputStream baos) {
 		baos.write( m_bytes, m_offset, m_length );
 	}
+	
+	/** Returns true if this is or can be made into a number */
+	public boolean isNumber() {
+		return ! this.luaToNumber().isNil();
+	}
+
 
 }
diff --git a/src/core/org/luaj/vm/LValue.java b/src/core/org/luaj/vm/LValue.java
index d1c446f6..0122315a 100644
--- a/src/core/org/luaj/vm/LValue.java
+++ b/src/core/org/luaj/vm/LValue.java
@@ -350,4 +350,14 @@ public class LValue {
 	public boolean isUserData() {
 		return false;
 	}
+
+	/** Returns true if this is or can be made into a number */
+	public boolean isNumber() {
+		return false;
+	}
+	
+	/** Returns true if this is a lua closure, false otherwise */
+	public boolean isClosure() {
+		return false;
+	}
 }
diff --git a/src/core/org/luaj/vm/LuaState.java b/src/core/org/luaj/vm/LuaState.java
index 6ac7985e..be41c312 100644
--- a/src/core/org/luaj/vm/LuaState.java
+++ b/src/core/org/luaj/vm/LuaState.java
@@ -2524,4 +2524,6 @@ public class LuaState extends Lua {
     		top = oldtop;
     	}
 	}
+    
+    
 }