Re: declare function/macro private

["Paul W. Rankin" via "Emacs development discussions." <emacs-devel@gnu.org>]

> On 7 Jun 2021, at 6:12 am, Stefan Monnier <monnier@iro.umontreal.ca> wrote:
> 
> Tassilo Horn [2021-06-06 20:12:49] wrote:
>> Stefan Monnier <monnier@iro.umontreal.ca> writes:
>>> I think the "--" convention actually includes an extra information
>>> compared to yours which could be useful here: we could warn for uses
>>> of "foo--" if and only if the use appears in something whose name
>>> doesn't start with "foo-".
>>> 
>>> IOW, use the string before the "--" as the definition of the "library"
>>> (so that would support cases where a library is spread over several
>>> files, as well as the case where a single file contains "internal
>>> libraries").
>> 
>> If my package was structured like
>> 
>>  foo.el
>>  foo-search.el
>>  foo-parse.el
>> 
>> I'd find it quite natural to name a private function in foo-search.el
>> `foo-search--do-stuff'.  Of course, it's ok if my `foo-base-do-stuff'
>> function from foo.el calls it but it would trigger a warning with your
>> approach because the "library" would be foo-search, no?
> 
> Indeed, the idea is that you'd have to use foo--search-do-stuff for
> those functions which are private to your foo package but not to
> foo-search.el, whereas you'd use foo-search--do-stuff for functions
> which are not only private to your package but even private to
> foo-search.el.

If there is a lake with a bunch of alligators in it, it would be a good thing to put up a sign that says "Danger: No swimming, Alligators".

Such a sign's sole purpose is to provide warning to people considering swimming in the alligator-infested lake, it does not actually prevent them from being eaten by alligators should they ignore the warning.

What I'm suggesting is to put up the sign, not to figure out a way to prevent alligators from eating swimmers who ignore the sign.