//*
// * Checks if the next tokens match a production pattern
// * alternative. The pattern alternative look-ahead set will be
// * used if existing, otherwise this method returns false.
// *
// * @param alt the pattern alternative to check
// *
// * @return true if the next tokens match, or
// * false otherwise
//
private bool IsNext(ProductionPatternAlternative alt)
{
LookAheadSet @set = alt.LookAhead;
if (@set == null)
{
return(false);
}
else
{
return(@set.IsNext(this));
}
}
//*
// * Checks if the next tokens match a production pattern. The
// * pattern look-ahead set will be used if existing, otherwise
// * this method returns false.
// *
// * @param pattern the pattern to check
// *
// * @return true if the next tokens match, or
// * false otherwise
//
private bool IsNext(ProductionPattern pattern)
{
LookAheadSet @set = pattern.LookAhead;
if (@set == null)
{
return(false);
}
else
{
return(@set.IsNext(this));
}
}
//*
// * Checks if the next tokens match a production pattern
// * element. If the element has a look-ahead set it will be
// * used, otherwise the look-ahead set of the referenced
// * production or token will be used.
// *
// * @param elem the pattern element to check
// *
// * @return true if the next tokens match, or
// * false otherwise
//
private bool IsNext(ProductionPatternElement elem)
{
LookAheadSet @set = elem.LookAhead;
if (@set != null)
{
return(@set.IsNext(this));
}
else if (elem.IsToken())
{
return(elem.IsMatch(PeekToken(0)));
}
else
{
return(IsNext(GetPattern(elem.Id)));
}
}
//*
// * Throws a parse exception that matches the specified look-ahead
// * set. This method will take into account any initial matching
// * tokens in the look-ahead set.
// *
// * @param set the look-ahead set to match
// *
// * @throws ParseException always thrown by this method
//
private void ThrowParseException(LookAheadSet @set)
{
Token token = default(Token);
ArrayList list = new ArrayList();
int[] initials = null;
// Read tokens until mismatch
while (@set.IsNext(this, 1))
{
@set = @set.CreateNextSet(NextToken().Id);
}
// Find next token descriptions
initials = @set.GetInitialTokens();
for (int i = 0; i <= initials.Length - 1; i++)
{
list.Add(GetTokenDescription(initials[i]));
}
// Create exception
token = NextToken();
throw new ParseException(ParseException.ErrorType.UNEXPECTED_TOKEN, token.ToShortString(), list, token.StartLine, token.StartColumn);
}