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Re: Clearing the screen and other such things.
- To: Kent M Pitman <KMP@SCRC-STONY-BROOK>
- Subject: Re: Clearing the screen and other such things.
- From: Jim Meehan <Meehan@YALE.ARPA>
- Date: Mon, 29 Jul 85 10:57:46 EDT
- Cc: COMMON-LISP@SU-AI
- In-reply-to: Kent M Pitman <KMP@SCRC-STONY-BROOK.ARPA>, Fri, 26 Jul 85 14:49 EDT
I'm afraid I agree with most of the criticism of your proposal. It
all sounds a little odd in an age where bitmaps and variable-width
fonts are so popular. The fact that you propose functions to erase
the character in front of the cursor and behind the cursor but not
*at* the cursor suggests that you yourself are accustomed to something
smarter than a glass teletype.
In any case, I wanted specifically to object to your use of VALUES:
... It should be possible to say
(SETF (CHARACTER-POSITION) (VALUES x y))
to later restore the cursor to the given coordinates.
VALUES is an "upward only" construction, and special forms
notwithstanding, you're trying to pass multiple values to the "setter"
of CHARACTER-POSITION. Granted, VALUES is asymmetric, and
(MULTIPLE-VALUE-CALL SET-CHARACTER-POSITION (VALUES x y)) is uglier,
but VALUES in CL is a first attempt at providing a notation for passing
values to the continuation of the caller, not a substitute for CONS.