RE: M-= in Dired

["Drew Adams" <drew.adams@oracle.com>]

> In Dired, M-= is bound to dired-backup-diff.  This is no good; there's
> no good reason for Dired to override the global binding for M-=, which
> is count-words-region.

Actually, there is no good reason for the global binding of `M-=' to
`count-words-region' either.

It is wasteful of a perfectly good repeatable key for `M-=' to be bound to
`count-words-region', which is not a usefully repeatable command.  You won't be
holding down `M-=' to repeat `count-words-region' multiple times.

It would be far better to bind `count-words-region' to something like `C-x M-=',
and thus keep `M-=' free.

It makes sense to use `M-=' for a repeatable action or perhaps as a prefix key
for grouping things that are mnemonic with an equals sign.  I use `C-=', for
example, as a prefix key for various comparisons:

C-= b         ediff-buffers
C-= d         diff
C-= e, C-= f  ediff-files

An equals sign can be suggestive of comparing things or of calculating/printing
a result, and no doubt of other things as well.  (Emacs sometimes uses `:' for
the showing a result, as in `M-:'.)

The point is that we do not have a very good reason for sacrificing `M-=' to a
one-off command like `count-words-region'.  Sure, that's a good command to bind
to some key, but let's bind it to `C-x M-=' or another key that is not so useful
as either a repeatable key or a prefix key.

> If there are no objections, I will simply unbind dired-backup-diff,
> and improve the behavior of = (dired-diff) so that it uses any existing
> backup file as the minibuffer input default, like M-x diff does.

No objection about that from me.  But I would prefer that we find a different
binding for `count-words-region', for the reasons given above.