internal override string ToString(ref int length)
{
var tag= ShorthandTag() == "!!str" ? "" : ShorthandTag() + " ";
length -= tag.Length + 1;
if ( length <= 0 )
return tag + "\"" + "...";
if ( Value.Length > length )
return tag + "\"" + Value.Substring(0, length) + "...";
length -= Value.Length + 1;
return tag + "\"" + Value + "\"";
}