bug#59305: 29.0.50; keymap-global-set handling of string bindings different from global-set-key

[Stefan Monnier via "Bug reports for GNU Emacs, the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>]

>> Whilst not strictly a regression, this behaviour is confusing and
>> unhelpful, and the solution is not easily found. I can think of two
>> solutions:
>>
>> 1. Change `kbd' to always return a vector even if the input is
>> ascii-only, which makes [4] work

`key-parse` always returns a vector.

>> 2. Change `keymap-set' to convert ascii-only strings to the format in
>> [5] or [6]. Probably just a call to `string-to-vector' is enough.
>
> I feel like the second alternative goes against the design of
> `keymap-global-set', where the idea explicitly was to only support a KEY
> argument that is `key-valid-p'.

The problem with 2 is that it requires a heuristic that tries to guess
which kind of string it is (either the good "new" kbd-style or the old
bad event-sequence).  This *will* misfire sooner or later.

>> (string-to-vector "foo") will do. But that just highlights the problem
>> even more: if itʼs that simple, why canʼt `keymap-global-set' do that
>> internally instead of forcing users to jump through hoops?
> AFAIU, because otherwise we can't have error handling for common typos,
> such as:

It's worse than that: we cannot reliably know whether the user meant for
the string to be a kbd-style description of events or a "raw" sequence
of events.

E.g. should

    (keymap-global-set <foo> "C-a")

remap that <foo> sequence to [?\C-a] or to [?C ?- ?a]?

> Then perhaps we should just change the docstrings and manual to
> explain that binding a key to a string of characters should use
> `kmacro' (since `kbd' is not the right thing for ASCII-only entry)

I fully support this: I think we should phase out the
use of strings/vectors as commands.


        Stefan