private AlternativeNode ParseAlternativeRest()
{
switch (CurToken.Type)
{
case TokenType.ALTERNATIVE:
AdvanceInput();
var mFactors = ParseMatchFactorList();
var af = new AlternativeNode(mFactors);
af.Next = ParseAlternativeRest();
return af;
case TokenType.CLOSEGROUP:
case TokenType.ENDANCHOR:
case TokenType.EOF:
return null;
default:
throw new ParseException("Invalid input lookahead");
}
}
public RegexNode(AlternativeNode firstAlternative = null, bool startAnchor = false, bool endAnchor = false)
{
StartAnchor = startAnchor;
EndAnchor = endAnchor;
FirstAlternative = firstAlternative;
}
private RegexNode ParseRegexBody()
{
switch (CurToken.Type)
{
case TokenType.OPENCLASS:
case TokenType.OPENCLASSNEGATE:
case TokenType.CHAR:
case TokenType.OPENGROUP:
case TokenType.OPENGROUPNOCAP:
case TokenType.ANY:
case TokenType.ALTERNATIVE: //will result in null from ParseMatchFactorList()
var mf = ParseMatchFactorList();
var af = new AlternativeNode(mf);
af.Next = ParseAlternativeRest();
return new RegexNode(firstAlternative: af);
default:
throw new ParseException("Invalid input lookahead (I think I need to be more generous here?)");
}
}
public AlternativeNode(MatchFactorNode firstFactor = null, AlternativeNode next = null)
{
Next = next;
FirstFactor = firstFactor;
}