Method isValid

src/backend/gsl/ExpressionParser.cpp:287–321

}

bool ExpressionParser::isValid(const QString& expr, const QStringList& vars) {
	QDEBUG(Q_FUNC_INFO << ", expr:" << expr << ", vars:" << vars);
	if (expr.isEmpty())
		return true;

	gsl_set_error_handler_off();

	Parser parser(false);
	parser.setSkipSpecialFunctionEvaluation(true);

	for (const auto& var : vars)
		parser.assign_symbol(qPrintable(var), 0);

	// Row index
	parser.assign_symbol("i", 0);

	const auto numberLocale = QLocale();
	DEBUG(Q_FUNC_INFO << ", number locale: " << STDSTRING(numberLocale.name()))
	parser.parse(qPrintable(expr), qPrintable(numberLocale.name()));

	// if parsing with number locale fails, try default locale
	if (parser.parseErrors() > 0) {
		DEBUG(Q_FUNC_INFO << ", WARNING: failed parsing expr \"" << STDSTRING(expr) << "\" with locale " << numberLocale.name().toStdString()
						  << ", errors = " << parser.parseErrors())
		parser.parse(qPrintable(expr), "en_US");
		if (parser.parseErrors() > 0)
			DEBUG(Q_FUNC_INFO << ", ERROR: parsing FAILED, errors = " << parser.parseErrors())
	}

	/* remove temporarily defined symbols */
	for (const auto& var : vars)
		parser.remove_symbol(qPrintable(var));

	return parser.parseErrors() == 0;
}

QStringList ExpressionParser::getParameter(const QString& expr, const QStringList& vars) {
	QDEBUG(Q_FUNC_INFO << ", variables:" << vars);