bug#7150: 23.2.50; Include patch for distinguishing between left and right Alt keys on OSX

[Jakub Turski <yacoob@gmail.com>]

It's not a bug per se, rather a feature request.
Would it be possible to include this patch:
http://lists.aquamacs.org/pipermail/aquamacs-devel/2009-November/003853.html
in Gnu Emacs? It's only relevant for OSX, but makes life easier for
anyone who wants to use Emacs under OSX and uses a keyboard layout that
uses right Alt key as a modifier to input special characters. This is an
Aquamacs patch, and Aquamacs allows this:

;; Make right Meta a system modifier.
(setq ns-right-alternate-modifier nil)

which results in left Alt being interpreted by Aquamacs as Meta, and
right Alt being interpreted by operating system as keyboard
modifier. This allows me to use Polish keyboard layout without resorting
to unusual method of inputting Polish characters. It would be good if
other users, especially those that don't want to use Aquamacs because of
some of its modifications, can use this feature.

I've tried to naively apply this patch to current 23.2 sources, but
failed - apparently it has diverged too much by now. I don't think I
have both skills and time needed to modify this patch, but it looks
relatively simple, provided you know your way around Emacs source code.

Is there a chance to port and include this feature?

Thanks,

KT.

In GNU Emacs 23.2.50.2 (x86_64-apple-darwin10.4.0, NS apple-appkit-1038.32)
 of 2010-10-02 on imacoob.nerv.local
Windowing system distributor `Apple', version 10.3.1038
configured using `configure  '--with-ns''

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: pl_PL.UTF-8
  value of $LC_CTYPE: pl_PL.UTF-8
  value of $LC_MESSAGES: C
  value of $LC_MONETARY: en_IE.utf-8
  value of $LC_NUMERIC: en_IE.utf-8
  value of $LC_TIME: en_IE.utf-8
  value of $LANG: en_IE.UTF-8
  value of $XMODIFIERS: nil
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

Major mode: Fundamental

Minor modes in effect:
  global-whitespace-mode: t
  tooltip-mode: t
  mouse-wheel-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
C-x 1 M-x r e p o r t - e m a <tab> <return>

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.

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