Improve calling convention handling when the number of arguments doesn't match the expected number, and the number of return values doesn't match those needed.

src/main/java/lua/value/LTable.java

@@ -50,15 +50,14 @@ public class LTable extends LValue {
 		}
 
 		// perform a lua call
-		public void luaStackCall(StackState state, int base, int nresults) {
+		public int luaStackCall(StackState state, int base, int nargs) {
 			if ( e.hasMoreElements() ) {
 				LValue key = (LValue) e.nextElement();
 				state.stack[base] = key;
 				state.stack[base+1] = t.luaGetTable(key);
-			} else {
-				state.stack[base] = LNil.NIL;
+				return 2;
 			}
-			
+			return 0;			
 		}
 	}
 

src/main/java/lua/value/LValue.java

@@ -14,9 +14,10 @@ public class LValue {
 		return true;
 	}
 
-	// perform a lua call
-	public void luaStackCall(StackState state, int base, int nargs) {
+	// perform a lua call, return number of results actually produced
+	public int luaStackCall(StackState state, int base, int nargs) {
 		luaUnsupportedOperation();
+		return 0;
 	}
 
 	// unsupported except for numbers