bug#5193: 23.1; single-key-description problem

[Stefan Monnier]

>> The character range (128 . 4194303) is bound to `self-insert-command'.
>> (single-key-description 128) gives "\200"
>> (single-key-description 4194303) gives "\377"
>> However, in the former case, "\200" is a string with one character,
>> \200. In the latter case, "\377" is a string with four characters, \,
>> 3, 7, and 7.
> Something seems to have changed here:
> (single-key-description 128) => "€"

This change is just the result of the switch from emacs-mule in
Emacs-22 to emacs-unicode in Emacs≥23 (i.e. 128 doesn't mean the same
char any more).

> (single-key-description 4194303) => "\301\277"
> But it's essentially still the same -- the 128 is a string of one
> character, and the other one is a string of 8 characters.
> I have no idea whether this is a bug or a feature, though.

Showing the internal representation of byte characters is clearly a bug.
I.e. (single-key-description 4194303) could/should return something like
"\377" either as a single char or as 4 chars.


        Stefan