public override bool TryMatchCurrent(LexerBuilder lexer)
{
var prev = lexer.Previous;
var first = lexer.Current;
// check for keywords
if (lexer.IsDelimiter(prev, true) && char.IsLetter(first))
{
// can be a keyword...
var sb = new StringBuilder();
sb.Append(lexer.Current);
while (!lexer.EndOfInput && char.IsLetter(lexer.PeekNext()))
{
sb.Append(lexer.Current);
}
if (keywords.Contains(sb.ToString()))
{
if (!lexer.EndOfInput)
{
lexer.RollbackBy(1);
}
lexer.Commit();
return(true);
}
return(false);
}
else
{
return(false);
}
}
public override bool TryMatchCurrent(LexerBuilder lexer)
{
// previous character must be delimiter, whitespace, or alphanumeric.
if (!lexer.IsDelimiter(lexer.Previous, true, true))
{
return(false);
}
if (IsSymbol(lexer.Current))
{
do
{
lexer.Commit();
lexer.PeekNext();
}while (IsSymbol(lexer.Current));
return(true);
}
return(false);
}
public override bool TryMatchCurrent(LexerBuilder lexer)
{
// previous character must be whitespace or delimiter
if (!lexer.IsDelimiter(lexer.Previous, true))
{
return(false);
}
if (!IsNumeric(lexer.Current))
{
return(false);
}
while (!lexer.EndOfInput)
{
lexer.Commit();
if (!IsNumeric(lexer.PeekNext()))
{
break;
}
}
return(true);
}