Re: Modifier Keys and the Archaic Meta Key

[Christopher Dimech]

If you look at Emacs Built-In Key Bindings using "C-h b", you will notice
that many bindings use the Control Key "C-" (Priority 1).  The Meta Key was
used as an Alternate Control Key for other commands and is less numerous than
commands with "C-".

On the original Lisp Machine Keyboards, the Control key was the key adjacent to
the Space Bar, and was used because it was the easiest key to reach (hence
Priority 1). On newer keyboards, the Control Key is the third key away from the
Space Bar.  This make "C-" more difficult to use.  Hence there are some 
(including
myself) who remap the key to be the one closest to the Space Bar as in the 
Original
Lisp Keyboards.

The Meta key was the next key closest to the Control Key.  Hence Priority 2, as
it started to be used for commands that had already been binded to "C-".

The Hyper (H), Shift (S) and Super (s) Modifier keys were not really used, but 
users could
use them for their own keybindings so the Emacs Built-In Commands could be 
retained.

The Shift key was between the Control Key and the Meta Key.  Perhaps the Shift 
Key can be
assigned Priority 3.  There followed by the Super and finally by the Hyper Key, 
furthest
away.

Thus in sequence from farthest to closest from Space Bar, the Modifier 
Mnemonics are
{H,s,S,M,C}.  My argument is to have them {s,S,H,M,C}.  This remapping makes 
User
Defined Key Bindings next to the Principal Emacs Modifier Keys {M,C}.  The 
Shift Key
is used for a very limited commands (e.g., C-M-S).  This gives idea of priority.

Thus we can choose user defined keys with Hyper to be Priority 3, and let the 
Shift
Key become secondary to the Hyper.  Currently, the Mnemonic for the Super Key is
small letter "s", which can be regarded as the lowest priority key of the five
modifier keys that are used by Emacs Users.  Have suggested to also add Modifier
Mnemonic P, in addition to 's', because Modifier Keys are customarily Upcase 
Letters,
except for the Super Key (thusly use the middle letter and Capitalise it).

The considerations mentioned bring an easier and more organised approach to Key
Bindings, similar the the original ideas around the topic.  Today we have lost
such organised approach and we just bundle all keys with equal regard.  A 
situation
that has always got problematic to those trying to make sense to the many 
built-in
key-bindings in Emacs and how to pragmatically construct one's own.

Just as Guy Steele reconciled the six different Emacs Keybindings Sets of the 
time,
I am working to do the same for the new generation of Keyboards with more 
possibilities
for constructing one's own.  This has become vital particularly following the 
development
of Keyboard Variants such as Colemak (most suitable for the English Language) 
and Dvorak
(for other languages, especially non-latin ones).  There are also the mechanical
keyboard today with the Cherry MX Speed or Silver Switches that travel only 1.2 
mm
rather than the standard 2mm, and require 45g of Actuation Force in contrast to 
the 50g for
Cherry MX Blues and the 60g for Cherry MX Blacks.

I am currently using the Cherry MX Silver myself.

Regards
Christopher


> Sent: Sunday, October 25, 2020 at 8:57 PM
> From: "Francis Belliveau" <f.belliveau@comcast.net>
> To: No recipient address
> Cc: "Help Gnu Emacs" <help-gnu-emacs@gnu.org>
> Subject: Re: Modifier Keys and the Archaic Meta Key
>
>
>
> > On Oct 25, 2020, at 08:49, Christopher Dimech <dimech@gmx.com> wrote:
> >
> >
> > Not instantly, that is agreed. But we can start with adding
> > the Key-Mnemonics 'A' and 'P'. We can call the key with Priority
> > 2, the Alternate Key 'A'.
> >
> > So nomenclature will be, by priority and Mnemonics:
> >
> > Control (C), Alternate (A,M), Hyper(H), Shift(S), Super(P,s).
>
> It seems that I have been left in the dark somewhere along the line.  I do 
> not understand the concept of "priorities" in this context.
> I have been using Emacs since the 1980's.
> As I see it there are three modifier keys: Shift,Control and what Emacs calls 
> Meta.  In general, Shift does not have meaning since it only changes the 
> character that the other modifiers apply to (C-a versus C-A or C-, versus 
> C-<).
> I have always understood that what the Emacs documentation referred to as 
> "the Meta Key" as the other modifier key used by the current OS or setup.
> As I understand things the modifier keys apply, period.  C-M-a has no 
> relationship to either C-a or M-a so where does priority come into play here?
>
> Fran
>