diff --git a/AST.cpp b/AST.cpp
index fd8f45a73..cdbfb4e9a 100644
--- a/AST.cpp
+++ b/AST.cpp
@@ -114,18 +114,10 @@ std::string FunctionDefinition::getCanonicalSignature()
 {
 	auto parameters = getParameters();
 	std::string ret = getName() + "(";
-	unsigned int i = 1;
 
-	for (ASTPointer<VariableDeclaration> const& member: parameters)
-	{
-		ret += member->getType()->toString();
-		if (i != parameters.size()) {
-			ret += ",";
-		}
-		i++;
-	}
-	ret += ")";
-	return ret;
+	for (auto it = parameters.cbegin(); it != parameters.cend(); ++it)
+		ret += (*it)->getType()->toString() + (it + 1 == parameters.end() ? "" : ",");
+	return ret + ")";
 }
 
 void Block::checkTypeRequirements()
diff --git a/Types.cpp b/Types.cpp
index 71319c3ac..640a34ca8 100644
--- a/Types.cpp
+++ b/Types.cpp
@@ -452,6 +452,17 @@ unsigned FunctionType::getSizeOnStack() const
 	}
 }
 
+std::string FunctionType::getCanonicalSignature() const
+{
+	auto parameters = getParameterTypes();
+	std::string ret = "NAME("; //TODO: how to get function name from FunctionType
+
+	for (auto it = parameters.cbegin(); it != parameters.cend(); ++it)
+		ret += (*it)->toString() + (it + 1 == m_parameterTypes.end() ? "" : ",");
+
+	return ret + ")";
+}
+
 bool MappingType::operator==(Type const& _other) const
 {
 	if (_other.getCategory() != getCategory())
diff --git a/Types.h b/Types.h
index 48539a1d7..0fe685b87 100644
--- a/Types.h
+++ b/Types.h
@@ -325,6 +325,7 @@ public:
 	virtual unsigned getSizeOnStack() const override;
 
 	Location const& getLocation() const { return m_location; }
+	std::string getCanonicalSignature() const;
 
 private:
 	TypePointers m_parameterTypes;