bug#30043: 25.3; C-M-e inserts euro character

[Tomas Nordin <tomasn@posteo.net>]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Tomas Nordin <tomasn@posteo.net>
>> Cc: 30043@debbugs.gnu.org
>> Date: Sun, 13 Oct 2019 12:00:40 +0200
>> 
>> Tomas Nordin <tomasn@posteo.net> writes:
>> 
>> > this strange behavior. Who knows, maybe there is something strange
>> > going on on all Windows installations at my work place.
>> 
>> I have now found one more person in this country (Sweden) who use emacs
>> on MS-Windows, outside my organisation, who complains about the same
>> thing. C-M-e inserts a euro character. Actually he didn't complain, but
>> I managed to get him to try this out and he confirmed the effect. Maybe
>> for the sake of this bug report we can pretend that he complained. His
>> version of emacs was
>> 
>>         GNU Emacs 26.2 (build 1, x86_64-w64-mingw32) of 2019-04-13
>
> Can you try setting w32-recognize-altgr to a nil value?

Here is a test session including w32-recognize-altgr

emacs -Q

w32-recognize-altgr ;; -> t
w32-use-fallback-wm-chars-method ;; -> nil

C-h c on the following key combinations and its message

Alt left-ctrl e -> € runs the command self-insert-command
AltGr left-ctrl e -> € runs the command self-insert-command
AltGr e -> € runs the command self-insert-command

(setq w32-recognize-altgr nil)

Alt left-ctrl e -> € runs the command self-insert-command
AltGr left-ctrl e -> € runs the command self-insert-command
AltGr e -> € runs the command self-insert-command

(setq w32-use-fallback-wm-chars-method t)

Alt left-ctrl e -> C-M-e runs the command end-of-defun
AltGr left-ctrl e -> C-M-e runs the command end-of-defun
AltGr e -> C-M-e runs the command end-of-defun

(setq w32-recognize-altgr t)

Alt left-ctrl e -> C-M-e runs the command end-of-defun
AltGr left-ctrl e -> € runs the command self-insert-command
AltGr e -> € runs the command self-insert-command


It seems that only nilling w32-recognize-altgr does not do it. Combining
w32-use-fallback-wm-chars-method as t and w32-recognize-altgr as nil
disables the AltGr functionality.

Best regards
--
Tomas