Add skeleton for contract level checker.

libsolidity/analysis/ContractLevelChecker.h

@@ -0,0 +1,59 @@
+/*
+	This file is part of solidity.
+
+	solidity is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	solidity is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with solidity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/**
+ * Component that verifies overloads, abstract contracts, function clashes and others
+ * checks at contract or function level.
+ */
+
+#pragma once
+
+#include <libsolidity/ast/ASTForward.h>
+
+#include <map>
+
+namespace langutil
+{
+class ErrorReporter;
+}
+
+namespace dev
+{
+namespace solidity
+{
+
+/**
+ * Component that verifies overloads, abstract contracts, function clashes and others
+ * checks at contract or function level.
+ */
+class ContractLevelChecker
+{
+public:
+	/// @param _errorReporter provides the error logging functionality.
+	explicit ContractLevelChecker(langutil::ErrorReporter& _errorReporter):
+		m_errorReporter(_errorReporter)
+	{}
+
+	/// Performs checks on the given contract.
+	/// @returns true iff all checks passed. Note even if all checks passed, errors() can still contain warnings
+	bool check(ContractDefinition const& _contract);
+
+private:
+	langutil::ErrorReporter& m_errorReporter;
+};
+
+}
+}