--- a/src/include/compiler/NodeFactory.h
+++ b/src/include/compiler/NodeFactory.h
@@ -15,7 +15,7 @@
 
 bool lt(std::vector<double> const &value1, std::vector<double> const &value2);
 bool lt(double const *value1, double const *value2, unsigned int length);
-bool lt(Node const *node1, Node const *node2);
+//bool lt(Node const *node1, Node const *node2);
 bool lt(std::vector<Node const *> const &par1, 
 	std::vector<Node const *> const &par2);