/// <summary>
/// Returns a ParseExpression by processing a suffix token.
/// </summary>
static object ProcessSuffix(Token token, ParseContext context, object[] args)
{
var expression = (ParseExpression)token[0].Tag;
// Wrap the expression if a quantifier is present
if (token.ChildCount > 1) {
var quantifier = context.MatchedText(token[1]);
if (quantifier.StartsWith("?"))
return new Optional(expression);
if (quantifier.StartsWith("*"))
return new ZeroOrMore(expression);
return new OneOrMore(expression);
}
return expression;
}
/// <summary>
/// Returns an identifier string by processing an identifier token.
/// </summary>
static object ProcessIdentifier(Token token, ParseContext context, object[] args)
{
return context.MatchedText(token[0]);
}
/// <summary>
/// Returns a PatternTerminal by processing a literal token.
/// </summary>
static object ProcessRegexLiteral(Token token, ParseContext context, object[] args)
{
var pattern = context.MatchedText(token[0]);
pattern = PatternTerminal.Unescape(pattern);
return new PatternTerminal(pattern);
}
/// <summary>
/// Returns a CustomMatcherTerminal by processing a custom matcher
/// literal token.
/// </summary>
static object ProcessCustomMatcher(Token token, ParseContext context, object[] args)
{
var matcherName = context.MatchedText(token[0]);
matcherName = matcherName.Substring(1, matcherName.Length - 2);
return new CustomMatcherTerminal(matcherName);
}