INTERFACE MGRd;

IMPORT
  PaintOp, Rd, TextPort, VTDef;

TYPE
  T <: Rd.T;

TYPE
  Style = RECORD
            intervalStyle: VTDef.IntervalStyle;
            bg, fg       : PaintOp.T;
          END;

CONST
  PastStyle = Style{intervalStyle := VTDef.IntervalStyle.GrayStyle, bg :=
                    PaintOp.Bg, fg := PaintOp.Fg};

  FutureStyle = Style{intervalStyle := VTDef.IntervalStyle.NoStyle, bg :=
                      PaintOp.Bg, fg := PaintOp.Fg};

PROCEDURE FromTextPort (         tp     : TextPort.T;
                        READONLY present: Style;
                        READONLY past                  := PastStyle;
                        READONLY future                := FutureStyle): T;

Returns a reader on tp. Read actions on the reader are reflected in the text port.

The postion of the textport preceding the current position of the reader will be displayed according to past. The character after the current position will be displayed in present and the remaining character in future.

Editing the textport while reading will have unpredictable results

END MGRd.