--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/luan/Lua.java	Tue Nov 13 05:54:32 2012 +0000
@@ -0,0 +1,56 @@
+package luan;
+
+
+public class Lua {
+
+	public static String toString(Object obj) {
+		if( obj == null )
+			return "nil";
+		return obj.toString();
+	}
+
+	public static String type(Object obj) {
+		if( obj == null )
+			return "nil";
+		if( obj instanceof String )
+			return "string";
+		if( obj instanceof Boolean )
+			return "boolean";
+		if( obj instanceof LuaNumber )
+			return "number";
+		return "userdata";
+	}
+
+	public static int length(Object obj) throws LuaException {
+		if( obj instanceof String ) {
+			String s = (String)obj;
+			return s.length();
+		}
+		if( obj instanceof LuaTable ) {
+			LuaTable t = (LuaTable)obj;
+			return t.length();
+		}
+		throw new LuaException( "attempt to get length of a " + type(obj) + " value" );
+	}
+
+	static LuaNumber toNumber(Object obj) throws LuaException {
+		if( obj instanceof LuaNumber )
+			return (LuaNumber)obj;
+		if( obj instanceof String ) {
+			String s = (String)obj;
+			try {
+				return new LuaNumber( Double.parseDouble(s) );
+			} catch(NumberFormatException e) {}
+		}
+		throw new LuaException( "attempt to perform arithmetic on a " + type(obj) + " value" );
+	}
+
+	static LuaNumber add(Object n1,Object n2) throws LuaException {
+		return new LuaNumber( toNumber(n1).n + toNumber(n2).n );
+	}
+
+	static LuaNumber sub(Object n1,Object n2) throws LuaException {
+		return new LuaNumber( toNumber(n1).n - toNumber(n2).n );
+	}
+
+}