public static bool IsApplicable(string source, int pos)
{
if (pos >= source.Length)
{
return(false);
}
return(FactorParser.IsApplicable(source, pos));
}
public static IExpression Parse(string source, ref int pos)
{
IExpression left = FactorParser.Parse(source, ref pos);
ParserImpl.SkipSpaces(source, ref pos);
if (pos == source.Length)
{
return(left);
}
if (source[pos] == '^')
{
pos++;
ParserImpl.SkipSpaces(source, ref pos);
if (!TermParser.IsApplicable(source, pos))
{
throw new ParserException("Invalid term at " + pos);
}
IExpression right = PowerParser.Parse(source, ref pos);
return(new PowerOperation(left, right));
}
return(left);
}