A TextSub.T represents a subsequence of another text.

INTERFACE TextSub;

TYPE
  TT <: Public;
  Public = TEXT OBJECT
    base  : TEXT;
    start : CARDINAL;
    len   : CARDINAL;
  END;

PROCEDURE New (t: TEXT;  start, length: CARDINAL): TEXT;

Return a sub-sequence of t: empty if start >= Length(t) or length = 0; otherwise the subsequence ranging from start to the minimum of start+length-1 and Length(t)-1.

END TextSub.