address feedback from review
diff --git a/tinyxml2.h b/tinyxml2.h
index a740dc3..864c8b9 100755
--- a/tinyxml2.h
+++ b/tinyxml2.h
@@ -265,6 +265,7 @@
     }

 

 	void SwapRemove(int i) {

+        TIXMLASSERT(i >= 0);

 		TIXMLASSERT(i < _size);

 		_mem[i] = _mem[_size - 1];

 		--_size;