private IEnumerable <ISymbol> Tokenize(string content, bool markup)
{
ITokenizer tok = MakeTokenizer(markup, new SeekableTextReader(content));
ISymbol sym;
ISymbol last = null;
while ((sym = tok.NextSymbol()) != null)
{
OffsetStart(sym, LocationTracker.CurrentLocation);
last = sym;
yield return(sym);
}
LocationTracker.UpdateLocation(content);
}