Copyright (C) 1992, Digital Equipment Corporation
All rights reserved.
See the file COPYRIGHT for a full description.
Last modified on Wed Jun 16 10:18:47 PDT 1993 by meehan
modified on Tue Feb 2 00:19:36 PST 1993 by mhb
modified on Tue Jun 16 13:08:41 PDT 1992 by muller
modified on Fri Mar 27 01:58:46 1992 by steveg
<* PRAGMA LL *>
<* PRAGMA SUBTYPE *>
A MarginFeedbackVBT is a multi-filter feedback that provides
visual feedback to the left of another VBT. This interface
defines a handful of useful ``left-hand sides.''
INTERFACE MarginFeedbackVBT;
IMPORT FeedbackVBT, Shadow, VBT;
TYPE
<* SUBTYPE T <: MultiFilter.T *>
T <: Public;
Public = FeedbackVBT.T OBJECT
METHODS
<* LL.sup <= VBT.mu *>
init (ch, marginVBT: VBT.T): T
END;
The following procedures create some popular types of
MarginFeedbackVBTs. See Figure~\ref{fig:marginfeedbacks}.
PROCEDURE NewCheck (ch: VBT.T; shadow: Shadow.T := NIL): T;
<* LL.sup <= VBT.mu *>
PROCEDURE NewBox (ch: VBT.T; shadow: Shadow.T := NIL): T;
<* LL.sup <= VBT.mu *>
PROCEDURE NewBullet (ch: VBT.T; shadow: Shadow.T := NIL): T;
<* LL.sup <= VBT.mu *>
END MarginFeedbackVBT.