[no subject]

[Howard I. Cannon <HIC at MIT-MC>]

cc: BUG-LISPM at MIT-AI

    Date: 30 August 1980 16:30-EDT
    From: Alec Destry <XCONOS at MIT-AI>
    To:   BUG-LISPM at MIT-AI

    Subject: unnecessary system changes.

      I have noticed over the past month or so a couple of
    not so useful system changes.
      One had to do with the :set-cursorpos message sent to a
    stream.  In system 29.95NWS it had this format:

      (funcall foobar-stream  ':character column line)
                              (or ':pixel)
      Get to system 30 and above it has this format:

      (funcall foobar-stream column line ':character)
The second format has always worked, while the first was only for compatibility
with the old system.  You should not have being using it in the first place.


      The second occurence has to do with tv:%draw-line.  In
    system 32.2 it has six arguments but in later systems it
    has seven arguments.  This time all my programs are broken.
    True it is easy enough to change but then I have to choose
    which lisp machine I want to work on.  This time I really
    have to choose cause there is no real enthusiasm to update
    to the latest system.
You probably should not be using the subprimitives.  Though sometimes
their use is indicated, usually it is not, and should instead be done by
sending messages to the stream.  The extra argument to %draw-line fixed a
very serious deficiency in the algorithm, and thus is certainly not gratuitous.