Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cornell!rochester!pt.cs.cmu.edu!sei!maa
From: maa@sei.cmu.edu (Mark Ardis)
Newsgroups: comp.emacs
Subject: Re: Minor modes
Message-ID: <8515@aw.sei.cmu.edu>
Date: 10 Feb 89 16:18:26 GMT
Organization: Carnegie-Mellon University (Software Engineering Institute), Pgh, PA
Lines: 21

If you think about it, minor modes *should* be harder to write than
major modes: A minor mode attempts to coexist peacefully with other
modes, whereas a major mode just redefines things from scratch
(mostly).

A minor-mode author needs to consider how his mode will interact with
several major modes and with several other minor modes.  To do this
successfully requires knowledge of the behavior of lots of modes.  For
example, if a minor mode invents new key-bindings, should those
bindings replace existing bindings or should they be added to the
existing ones?  If they are added, what conventions should be
followed?  (E.g., should the prefix be "^X" or "^C"?)  Note that most
of these issues have nothing to do with the *implementation* of the
new features, but have a lot to do with the *use* of the features.

Mark A. Ardis
Software Engineering Institute
Carnegie-Mellon University
Pittsburgh, PA 15213
(412) 268-7636
maa@sei.cmu.edu