    [NAME]
    ALL.dao.type.string.pattern.pfind

    [TITLE]
    string.pfind()

    [DESCRIPTION]

       1  string.pfind( pt :string, index = 0, start = 0, end = 0 )=>list<tuple<start:int,end:int> >

    This method searches for the position(s) of substring(s) that match(es) to the pattern
    represented by pt. If index is greater than zero, search for the index-th occurrence of
    the matched substring, otherwise, search for all. The searching starts from position
    start, and ends at end if it is greater than zero. Zero value for end indicates
    searching until the end of the string.