}
private EncodingSpec parse(String s) throws IOException, RecognitionException {
Reader reader = new StringReader(s);
CommonTokenStream input = new CommonTokenStream(new FormulaLexer(new ANTLRReaderStream(reader)));
FormulaParser tokenParser = new FormulaParser(input);
FormulaParser.expression_return parserResult = tokenParser.expression();
reader.close();
return parserResult.r;
}