public LessonSpan(StringWithIndex content, string startMarker, string endMarker)
: base(content)
{
StartMarker = startMarker;
EndMarker = endMarker;
OverrideContent(content.TrimStart(startMarker).TrimEnd(endMarker));
}
public static StringWithIndex Trim(this StringWithIndex text, params char[] chars)
{
return(text.TrimStart(chars).TrimEnd(chars));
}