bug#10940: Emacs 24: regression reading comma

bug#10940: Emacs 24: regression reading comma

[Chris Leyon]

In Emacs 23, the lisp reader correctly parses a comma when reading an
event modifier, as in the following example specifying the character
C-,
    (global-set-key [(control ,)] 'my-command)

The Emacs 24 reader gives the following error when parsing the same expression:
    Invalid read syntax: )

bug#10940: Emacs 24: regression reading comma

[Stefan Monnier]

> In Emacs 23, the lisp reader correctly parses a comma when reading an
> event modifier, as in the following example specifying the character
> C-,
>     (global-set-key [(control ,)] 'my-command)

You did not realize, but the above relies on the old-style backquote
syntax, which has been further phased out (it's been obsolete for a very
long time now).  So now (control ,) fails in the same way as (control
').  Use [(control ?,)] or [(control \,)] instead (which will work for
older emacsen as well).


        Stefan

bug#10940: Emacs 24: regression reading comma

[Chong Yidong]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

>> In Emacs 23, the lisp reader correctly parses a comma when reading an
>> event modifier, as in the following example specifying the character
>> C-,
>>     (global-set-key [(control ,)] 'my-command)
>
> You did not realize, but the above relies on the old-style backquote
> syntax, which has been further phased out (it's been obsolete for a very
> long time now).  So now (control ,) fails in the same way as (control
> ').  Use [(control ?,)] or [(control \,)] instead (which will work for
> older emacsen as well).

I've added a note to etc/NEWS about this.