Re: posix vs default mode nonsense

[Lawrence Velázquez]

On Mon, Oct 21, 2024, at 4:23 PM, Zachary Santer wrote:
> On Mon, Oct 21, 2024 at 11:53 AM Chet Ramey <chet.ramey@case.edu> wrote:
>>
>> On 10/21/24 9:54 AM, Robert Elz wrote:
>> >  From the earlier message (just replying to this one to get the
>> > new Subject: which fits better)...
>> >
>> > zsanter@gmail.com said:
>> >    | I can work around function names needing to be valid shell 'name's by
>> >
>> > That one bash could easily fix if it wanted to, there's never been a
>> > POSIX requirement that only "name"s can be used as function names.
>>
>> No, the original 1992 standard required it:
>>
>> "The function is named fname; it shall be a name (see 3.1.5)."
>>
>> That changed to an application requirement in 2001.
>
> Pardon my ignorance, but as an "application requirement," is that
> saying what shell scripts are allowed to do, rather than what bash
> itself is allowed to do?

Yes.  A shell is an "implementation", not an "application".

https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/V1_chap02.html#tag_02_01
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/V1_chap02.html#tag_02_02


> Don't know how much weight the Google Shell Style Guide carries here,
> or with the Austin Group, but:
>>  If you’re writing a package, separate package names with :: [in function 
>> names].
> https://google.github.io/styleguide/shellguide.html#function-names

Google uses default-mode bash almost exclusively, so their guide
is not relevant to a discussion about POSIX mode.

https://google.github.io/styleguide/shellguide.html#s1.1-which-shell-to-use


> Koichi Murase's ble.sh has a bunch of function names with '/', '-',
> '.', etc. in the names.
> https://github.com/akinomyoga/ble.sh/

I wouldn't be surprised if POSIX mode broke ble.sh in a number of
ways.  Using interactive shells in POSIX mode is surely uncommon.


> I've got some functions that look like I'm overloading the increment
> operator in C++:
> abc::++ () { ... }
> xyz::++ () { ... }
> ++ () { ... }
>
> Those functions spent some time as "increment"* before I realized I
> could do that, and I couldn't resist the urge.
>
> So my script might violate POSIX [...] I don't mind my script
> violating POSIX. It's probably not going to run in any other
> shell than bash anyway.

Yes, a script that uses those functions is nonconformant, but that
only matters if you're aiming for conformance in the first place.


> but POSIX allows shell implementations to work with those
> function names anyway?

Yes.


-- 
vq