Implemented common function for parsing expected values.

include/plasp/sas/Description.h

@@ -42,8 +42,6 @@ class Description
 	private:
 		Description();
 
-		void parseSectionIdentifier(std::istream &istream, const std::string &expectedSectionIdentifier) const;
-
 		const Variable &parseVariable(std::istream &istream) const;
 		const Value &parseValue(std::istream &istream, const Variable &variable) const;
 		AssignedVariable parseAssignedVariable(std::istream &istream) const;

include/plasp/utils/Parsing.h

@@ -3,6 +3,7 @@
 
 #include <exception>
 #include <iosfwd>
+#include <sstream>
 #include <string>
 #include <typeinfo>
 
@@ -38,6 +39,23 @@ T parse(std::istream &istream)
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////
 
+template<class T>
+void parseExpected(std::istream &istream, const T &expectedValue)
+{
+	const auto value = parse<T>(istream);
+
+	if (value == expectedValue)
+		return;
+
+	std::stringstream errorStream;
+
+	errorStream << "Invalid format, expected " << expectedValue << ", got " + value;
+
+	throw utils::ParserException(errorStream.str());
+}
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+
 }
 }