bug#31962: 27.0; imenu.el constructs - names and doc

[Eli Zaretskii <eliz@gnu.org>]

> Date: Sun, 24 Jun 2018 18:51:23 -0700 (PDT)
> From: Drew Adams <drew.adams@oracle.com>
> 
> 1. `imenu--generic-function' should not have a double-hyphen in its
> name.  It is the main function in the library, and it is explicitly
> referenced by multiple doc strings in the file

As long as this function is not autoloaded, we have no unequivocal
proof that it's the main function in the library.  A function that is
the workhorse of a library can legitimately be an internal function.

I agree that this case is somewhat borderline, but I don't have enough
time and energy to make the changes in the current system, because the
problems it creates sound very minor to me.

I made small fixes in 2 doc strings, but that's as far as I was
prepared to go in this case.

> including that of a user option
> (`imenu-generic-skip-comments-and-strings') and that of the
> principal configuration variable (`imenu-generic-expression'), which
> is defined per mode.

The doc string of imenu-generic-skip-comments-and-strings was one of
those I changed.

> 2. The doc string of `imenu--generic-function' says this, with zero
> description of INDEX-NAME INDEX-POSITION FUNCTION and ARGUMENTS:
> 
>   The return value is an alist of the form
>    (INDEX-NAME . INDEX-POSITION)
>   or
>    (INDEX-NAME INDEX-POSITION FUNCTION ARGUMENTS...)
>   The return value may also consist of nested index alists like:
>    (INDEX-NAME . INDEX-ALIST)
>   depending on PATTERNS.
> 
> Each of those pieces of the return value should be specified, not just
> named.

Not as long as this is an internal function.

> 3. Similarly, other functions and variables should be renamed to use a
> single, not a double, hyphen, starting with `imenu--sort-by-name' and
> `imenu--index-alist'.  I don't argue now that NO functions wnd variables
> in the library should have names declaring that they are internal, but a
> better judgment call is in order.

Likewise.

> We are documenting the structure and behavior of Imenu by referring to
> "internal" variables and functions.  That makes no sense - or rather, it
> points out how silly was declaring these to be "internal".

Please don't use "silly" to describe work of others, as doing so makes
the discussion much less pleasant.