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From: KFL@MC.LCS.MIT.EDU ("Keith F. Lynch")
Newsgroups: mod.computers.vax
Subject: Lone escapes
Message-ID: <[MC.LCS.MIT.EDU].851812.860315.KFL>
Date: Sat, 15-Mar-86 13:33:21 EST
Article-I.D.: <[MC.LCS.MIT.EDU].851812.860315.KFL>
Posted: Sat Mar 15 13:33:21 1986
Date-Received: Mon, 17-Mar-86 04:03:14 EST
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  Actually, recognition of lone escapes is not necessary for Emacs to
work right.  It is always unambiguous when a command ends.  If ESC-A
is a command then there is no ESC-A-B command.
  Of course this means you can run into difficulties when binding
commands to keys which producs escape sequences.  On an ANSI terminal,
most such keys produce ESC-[-something.  So ESC-[ cannot be a command
itself.  On non-ANSI terminals the arrow keys might generate ESC-A
ESC-B ESC-C and ESC-D.  So these commands cannot be used to mean
things other than what the arrow keys mean.  This is unfortunate since
these are well known Emacs commands.  The solution Gosling's Emacs
uses is to allow case-sensitive commands.  The up-arrow key might
produce ESC-A, and to go to the beginning of the sentence you have to
enter ESC-a (lowercase A).  The only problem with this is that some
people like to edit whith CAPS-LOCK on, and this makes it difficult.
  Another solution is to use timing hacks.  It has been pointed out
that this doesn't work through MUXes and networks as they only
guarantee that characters will be received in the right order (and
sometimes not even that!) but guarantee nothing about timing.  But
this is an excellent solution on microcomputers and other single user
machines.  Thus ESC-A would mean one thing while ESC (pause) A means
another.
  Of course these principles do not apply only to Emacs.  This is
important for any utility which uses arrow keys and/or function keys
and which also allows ESC commands.
								...Keith