/**
* 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;
ArrayList list = new ArrayList();
int[] initials;
// 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; i++)
{
list.Add(GetTokenDescription(initials[i]));
}
// Create exception
token = NextToken();
throw new ParseException(ParseException.ErrorType.UNEXPECTED_TOKEN,
token.ToShortString(),
list,
token.StartLine,
token.StartColumn);
}
/// <summary>
/// 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.
/// </summary>
/// <param name="set">The look-ahead set to match</param>
/// <exception cref="ParseException">Always thrown by this method</exception>
private void ThrowParseException(LookAheadSet set)
{
Token token;
IList <string> list = new List <string>();
int[] initials;
// Read tokens until mismatch
while (set.IsNext(this, 1))
{
set = set.CreateNextSet(this.NextToken().Id);
}
// Find next token descriptions
initials = set.InitialTokens;
for (int i = 0; i < initials.Length; i++)
{
list.Add(this.GetTokenDescription(initials[i]));
}
// Create exception
token = this.NextToken();
throw new ParseException(
ParseException.ErrorType.UnexpectedToken,
token.ToShortString(),
list,
token.StartLine,
token.StartColumn);
}
/**
* 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;
ArrayList list = new ArrayList();
int[] initials;
// 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; i++) {
list.Add(GetTokenDescription(initials[i]));
}
// Create exception
token = NextToken();
throw new ParseException(ParseException.ErrorType.UNEXPECTED_TOKEN,
token.ToShortString(),
list,
token.StartLine,
token.StartColumn);
}
