diff --git a/libsolidity/AST.cpp b/libsolidity/AST.cpp
index 1fa6d8f6f..629525210 100644
--- a/libsolidity/AST.cpp
+++ b/libsolidity/AST.cpp
@@ -110,6 +110,23 @@ void FunctionDefinition::checkTypeRequirements()
 	m_body->checkTypeRequirements();
 }
 
+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 += ",";
+		}
+	}
+	ret += ")";
+	return ret;
+}
+
 void Block::checkTypeRequirements()
 {
 	for (shared_ptr<Statement> const& statement: m_statements)
diff --git a/libsolidity/AST.h b/libsolidity/AST.h
index b7c3dc6c0..32cc23a5b 100644
--- a/libsolidity/AST.h
+++ b/libsolidity/AST.h
@@ -277,6 +277,12 @@ public:
 	/// Checks that all parameters have allowed types and calls checkTypeRequirements on the body.
 	void checkTypeRequirements();
 
+	/// Returns the canonical signature of the function
+	/// That consists of the name of the function followed by the
+	/// types of the arguments separated by commas all enclosed in parentheses
+	/// without any spaces
+	std::string getCanonicalSignature();
+
 private:
 	bool m_isPublic;
 	ASTPointer<ParameterList> m_parameters;