added parsing for constant variables

AST.cpp

@@ -197,7 +197,7 @@ vector<pair<FixedHash<4>, FunctionTypePointer>> const& ContractDefinition::getIn
 				}
 
 			for (ASTPointer<VariableDeclaration> const& v: contract->getStateVariables())
-				if (v->isPublic() && functionsSeen.count(v->getName()) == 0)
+				if (v->isPublic() && functionsSeen.count(v->getName()) == 0 && !v->isConstant())
 				{
 					FunctionType ftype(*v);
 					functionsSeen.insert(v->getName());
@@ -322,8 +322,8 @@ string FunctionDefinition::getCanonicalSignature() const
 
 bool VariableDeclaration::isLValue() const
 {
-	// External function parameters are Read-Only
-	return !isExternalFunctionParameter();
+	// External function parameters and constant declared variables are Read-Only
+	return !isExternalFunctionParameter() && !m_isConstant;
 }
 
 void VariableDeclaration::checkTypeRequirements()

AST.h

@@ -440,13 +440,22 @@ private:
 class VariableDeclaration: public Declaration
 {
 public:
-	VariableDeclaration(SourceLocation const& _location, ASTPointer<TypeName> const& _type,
-							ASTPointer<ASTString> const& _name, ASTPointer<Expression> _value,
+	VariableDeclaration(
+			SourceLocation const& _location,
+			ASTPointer<TypeName> const& _type,
+			ASTPointer<ASTString> const& _name,
+			ASTPointer<Expression> _value,
 			Visibility _visibility,
-							bool _isStateVar = false, bool _isIndexed = false):
+			bool _isStateVar = false,
+			bool _isIndexed = false,
+			bool _isConstant = false):
 		Declaration(_location, _name, _visibility),
-			m_typeName(_type), m_value(_value),
-			m_isStateVariable(_isStateVar), m_isIndexed(_isIndexed) {}
+		m_typeName(_type),
+		m_value(_value),
+		m_isStateVariable(_isStateVar),
+		m_isIndexed(_isIndexed),
+		m_isConstant(_isConstant){}
+
 	virtual void accept(ASTVisitor& _visitor) override;
 	virtual void accept(ASTConstVisitor& _visitor) const override;
 
@@ -465,6 +474,7 @@ public:
 	bool isExternalFunctionParameter() const;
 	bool isStateVariable() const { return m_isStateVariable; }
 	bool isIndexed() const { return m_isIndexed; }
+	bool isConstant() const { return m_isConstant; }
 
 protected:
 	Visibility getDefaultVisibility() const override { return Visibility::Internal; }
@@ -474,6 +484,7 @@ private:
 	ASTPointer<Expression> m_value;     ///< the assigned value, can be missing
 	bool m_isStateVariable;             ///< Whether or not this is a contract state variable
 	bool m_isIndexed;                   ///< Whether this is an indexed variable (used by events).
+	bool m_isConstant;                  ///< Whether the variable is a compile-time constant.
 
 	std::shared_ptr<Type const> m_type; ///< derived type, initially empty
 };

Compiler.cpp

@@ -276,13 +276,14 @@ void Compiler::registerStateVariables(ContractDefinition const& _contract)
 {
 	for (ContractDefinition const* contract: boost::adaptors::reverse(_contract.getLinearizedBaseContracts()))
 		for (ASTPointer<VariableDeclaration> const& variable: contract->getStateVariables())
+			if (!variable->isConstant())
 				m_context.addStateVariable(*variable);
 }
 
 void Compiler::initializeStateVariables(ContractDefinition const& _contract)
 {
 	for (ASTPointer<VariableDeclaration> const& variable: _contract.getStateVariables())
-		if (variable->getValue())
+		if (variable->getValue() && !variable->isConstant())
 			ExpressionCompiler(m_context, m_optimize).appendStateVariableInitialization(*variable);
 }
 

ExpressionCompiler.cpp

@@ -855,8 +855,11 @@ void ExpressionCompiler::endVisit(Identifier const& _identifier)
 	}
 	else if (FunctionDefinition const* functionDef = dynamic_cast<FunctionDefinition const*>(declaration))
 		m_context << m_context.getVirtualFunctionEntryLabel(*functionDef).pushTag();
-	else if (dynamic_cast<VariableDeclaration const*>(declaration))
+	else if (auto variable = dynamic_cast<VariableDeclaration const*>(declaration))
+	{
+		if (!variable->isConstant())
 			setLValueFromDeclaration(*declaration, _identifier);
+	}
 	else if (dynamic_cast<ContractDefinition const*>(declaration))
 	{
 		// no-op

Parser.cpp

@@ -135,6 +135,7 @@ ASTPointer<ContractDefinition> Parser::parseContractDefinition()
 		}
 		while (m_scanner->getCurrentToken() == Token::Comma);
 	expectToken(Token::LBrace);
+	bool isDeclaredConst = false;
 	while (true)
 	{
 		Token::Value currentToken = m_scanner->getCurrentToken();
@@ -152,13 +153,21 @@ ASTPointer<ContractDefinition> Parser::parseContractDefinition()
 			VarDeclParserOptions options;
 			options.isStateVariable = true;
 			options.allowInitialValue = true;
+			options.isDeclaredConst = isDeclaredConst;
 			stateVariables.push_back(parseVariableDeclaration(options));
+			isDeclaredConst = false;
 			expectToken(Token::Semicolon);
 		}
 		else if (currentToken == Token::Modifier)
 			modifiers.push_back(parseModifierDefinition());
 		else if (currentToken == Token::Event)
 			events.push_back(parseEventDefinition());
+		else if (currentToken == Token::Const)
+		{
+			solAssert(Token::isElementaryTypeName(m_scanner->peekNextToken()), "");
+			isDeclaredConst = true;
+			m_scanner->next();
+		}
 		else
 			BOOST_THROW_EXCEPTION(createParserError("Function, variable, struct or modifier declaration expected."));
 	}
@@ -348,7 +357,7 @@ ASTPointer<VariableDeclaration> Parser::parseVariableDeclaration(
 	}
 	return nodeFactory.createNode<VariableDeclaration>(type, identifier, value,
 									visibility, _options.isStateVariable,
-									isIndexed);
+									isIndexed, _options.isDeclaredConst);
 }
 
 ASTPointer<ModifierDefinition> Parser::parseModifierDefinition()

Parser.h

@@ -54,6 +54,7 @@ private:
 		bool allowIndexed = false;
 		bool allowEmptyName = false;
 		bool allowInitialValue = false;
+		bool isDeclaredConst = false;
 	};
 
 	///@{

Types.h

@@ -516,7 +516,7 @@ private:
 	std::vector<std::string> m_parameterNames;
 	std::vector<std::string> m_returnParameterNames;
 	Location const m_location;
-	/// true iff the function takes an arbitrary number of arguments of arbitrary types
+	/// true if the function takes an arbitrary number of arguments of arbitrary types
 	bool const m_arbitraryParameters = false;
 	bool const m_gasSet = false; ///< true iff the gas value to be used is on the stack
 	bool const m_valueSet = false; ///< true iff the value to be sent is on the stack