[OS X Emacs] Aquamacs Meta key

[Jean-Christophe Helary]

> On Mar 12, 2017, at 0:51, 7stud <7stud at excite.com> wrote:
> 
> Thereafter, every time I hit a Meta key sequence, e.g. M-p, a mathematical symbol, e.g. pi, gets entered into the buffer--rather than the emacs key sequence doing the expected operation.  This is very irritating.  Is there a way to permanently set the Meta key to my Option key? I don't want anything I type ever to be able to change which key is the Meta key. 

In recent versions of macOS, you can assign OPTION to be ESC. That way, your Meta will *always* be ESC and you can *always* access ESC with OPTION.

The setting is in System Preferences > Keyboard > (bottom right) Modifier Keys...
(The setting did not exist in El Capitan, and I think it only came with a recent update of Sierra).

> And, I would encourage the Aquamacs implementers to remove this "feature" forthwith.   Do you have any idea how frustrating it is when someone is trying to learn emacs, and the Meta key randomly changes, causing emacs key sequences not to work as described?? Do you think that beginners are going to be able to figure out why certain key sequences don't work, i.e. that their Meta key suddenly stopped being the Meta key? 

Exactly as Elliott said. There are excellent reasons to have OPTION remain a mod key for the keyboard. That's the way the Mac is designed. I personally type French, English and Japanese on a Qwerty JIS keyboard and I can do that because of the OPTION key. Mac is the only platform that allows that to happen out of the box.

So, if you're not on Sierra, just remember that Ctrl+; is what you need to change the input mod key.

On a side note, it seems to me Ctrl+; should revert to the input selected before typing it. Now it only toggles "Option is Meta" or "Option is not Meta", but if the user selects "... Meta & US" for ex, and reverts to "Option is not Meta", a further change should go back to "... Meta & US" and not "Option is Meta".

Jean-Christophe Helary