PgclParser: Do not reject variable names with a keyword as proper prefix. (fixes GitHub issue #84)

src/storm-pgcl/parser/PgclParser.cpp

@@ -111,7 +111,8 @@ namespace storm {
             expression.name("expression");
             booleanCondition  = expressionParser[qi::_val = phoenix::bind(&PgclParser::createBooleanExpression, phoenix::ref(*this), qi::_1)];
             uniformExpression = (qi::lit("unif") >> qi::lit("(") >> qi::int_ >> qi::lit(",") >> qi::int_ >> qi::lit(")"))[qi::_val = phoenix::bind(&PgclParser::createUniformExpression, phoenix::ref(*this), qi::_1, qi::_2)];
-            variableName     %= (+(qi::alnum | qi::lit("_"))) - invalidIdentifiers;
+            variableName     %= qi::as_string[qi::raw[qi::lexeme[((qi::alpha | qi::char_('_')) >> *(qi::alnum | qi::char_('_')))]]][qi::_pass = phoenix::bind(&PgclParser::isValidIdentifier, phoenix::ref(*this), qi::_1)];
+            
             variableName.name("variable name");
             programName      %= +(qi::alnum | qi::lit("_"));
             programName.name("program name");
@@ -181,6 +182,10 @@ namespace storm {
             return *result;
         }
 
+        bool PgclParser::isValidIdentifier(std::string const& identifier) {
+            return this->invalidIdentifiers.find(identifier) == nullptr;
+        }
+        
         storm::expressions::Variable PgclParser::declareDoubleVariable(std::string const& variableName) {
             storm::expressions::Variable variable = expressionManager->declareRationalVariable(variableName);
             this->identifiers_.add(variableName, variable.getExpression());

src/storm-pgcl/parser/PgclParser.h

@@ -140,6 +140,7 @@ namespace storm {
 
             // Constructors for the single program parts. They just wrap the statement constructors and throw exceptions in case something unexpected was parsed.
             storm::pgcl::PgclProgram createProgram(std::string const& programName, boost::optional<std::vector<storm::expressions::Variable> > parameters, std::vector<std::shared_ptr<storm::pgcl::VariableDeclaration>> const& variableDeclarations, std::vector<std::shared_ptr<storm::pgcl::Statement> > const& statements);
+            bool isValidIdentifier(std::string const& identifier);
             storm::expressions::Variable declareDoubleVariable(std::string const& variableName);
             std::shared_ptr<storm::pgcl::AssignmentStatement> createAssignmentStatement(std::string const& variableName, boost::variant<storm::expressions::Expression, storm::pgcl::UniformExpression> const& assignedExpression);
             std::shared_ptr<storm::pgcl::VariableDeclaration> createIntegerDeclarationStatement(std::string const& variableName, storm::expressions::Expression const& assignedExpression);