Handling of *ARGZERO options, for Zsh <= 5.3

Handling of *ARGZERO options, for Zsh <= 5.3

[Sebastian Gniazdowski]

Hello,
I want to filter out $0 value if it contains path to Zsh binary:

% echo ${${0:#$ZSH_ARGZERO}:-${(%):-%N}}

Above works, but for Zsh 5.3 and above. Is it possible to do this with earlier Zshells?

The goal is to have choice to avoid %N, because it cannot be altered, and to solve problems caused by *ARGZERO options. Altering $0 would allow to do `eval "$(<script)"', which can be faster. I'm actually doing a bit more, details are on http://zdharma.org/Zsh-100-Commits-Club/Zsh-Plugin-Standard.html

--  
Sebastian Gniazdowski
psprint /at/ zdharma.org

Re: Handling of *ARGZERO options, for Zsh <= 5.3

[dana]

On 2 Jan 2018, at 04:17, Sebastian Gniazdowski <psprint@zdharma.org> wrote:
>I want to filter out $0 value if it contains path to Zsh binary:

A lot of the time you won't have the path to the zsh binary; it will often just
be the base name:

  % print $ZSH_ARGZERO
  zsh

Even when you have a path you might need to deal with symlinks, &c. On mine
sometimes i'll have /usr/local/bin/zsh and other times it'll have been resolved
to /usr/local/Cellar/zsh/x.y.z/bin/zsh.

On 2 Jan 2018, at 04:17, Sebastian Gniazdowski <psprint@zdharma.org> wrote:
>Above works, but for Zsh 5.3 and above. Is it possible to do this with earlier Zshells?

If the problem is ZSH_ARGZERO, shouldn't this work in like 5.0+?

  () {
    setopt local_options posix_argzero
    MY_ARGZERO=$0
  }

dana

Re: Handling of *ARGZERO options, for Zsh <= 5.3

[Bart Schaefer]

On Tue, Jan 2, 2018 at 8:57 AM, dana <dana@dana.is> wrote:
>
> If the problem is ZSH_ARGZERO, shouldn't this work in like 5.0+?
>
>   () {
>     setopt local_options posix_argzero
>     MY_ARGZERO=$0
>   }

For considerably older (but still not the oldest) zsh you can use
$funcfiletrace:

zmodload zsh/parameter
print -r -- ${ZSH_ARGZERO:=${${funcfiletrace[-1]}[(ws/:/)1]}}

Re: Handling of *ARGZERO options, for Zsh <= 5.3

[Sebastian Gniazdowski]

On 2 stycznia 2018 at 20:35:33, Bart Schaefer (schaefer@brasslantern.com) wrote:
> On Tue, Jan 2, 2018 at 8:57 AM, dana wrote:
> >
> > If the problem is ZSH_ARGZERO, shouldn't this work in like 5.0+?
> >
> > () {
> > setopt local_options posix_argzero
> > MY_ARGZERO=$0
> > }
> 
> For considerably older (but still not the oldest) zsh you can use
> $funcfiletrace:
> 
> zmodload zsh/parameter
> print -r -- ${ZSH_ARGZERO:=${${funcfiletrace[-1]}[(ws/:/)1]}}

I'm always little afraid using this in non-debug code. Pitty that there's no at least prompt escape code (zsh var would be best) that would return path to binary.

-- 
Sebastian Gniazdowski
psprint /at/ zdharma.org

Re: Handling of *ARGZERO options, for Zsh <= 5.3

[dana]

On 2 Jan 2018, at 23:14, Sebastian Gniazdowski <psprint@zdharma.org> wrote:
>Pitty that there's no at least prompt escape code (zsh var would be best) that would return path to binary.

It's slightly irritating because there's no single cross-platform way to do it.
On Linux you can use /proc/self/exe, and some BSDs have a similar mechanism, but
then there's macOS and Solaris and AIX and so on.

I have wanted this feature in the past myself, though, so i would definitely be
in favour of a ZSH_EXECUTABLE_PATH or something. In fact i may look into it now
that you bring it up.

dana

Re: Handling of *ARGZERO options, for Zsh <= 5.3

[dana]

On 2 Jan 2018, at 23:27, dana <dana@dana.is> wrote:
>I have wanted this feature in the past myself, though, so i would definitely be
>in favour of a ZSH_EXECUTABLE_PATH or something. In fact i may look into it now
>that you bring it up.

This is how Perl handles it:

https://github.com/Perl/perl5/blob/3d10fa085102a79a96d9e335384c3f56f3b6b9cc/caretx.c

Seems rather tedious

dana

Re: Handling of *ARGZERO options, for Zsh <= 5.3

[Eric Cook]

Weird how the prompting, calender, zftp and completion system all work with fpath
and autoloading, yet `plugins' somehow need to depend on the exact location
of files to bootstrap themselves.

Re: Handling of *ARGZERO options, for Zsh <= 5.3

[Bart Schaefer]

On Tue, Jan 2, 2018 at 11:25 AM, Eric Cook <llua@gmx.com> wrote:
> Weird how the prompting, calender, zftp and completion system all work with fpath
> and autoloading, yet `plugins' somehow need to depend on the exact location
> of files to bootstrap themselves.

The thought is that plugins might be installed in non-standard
locations and might have multiple dependent files, so it's easier if
you don't have to put them all in a previously-known fpath.

Re: Handling of *ARGZERO options, for Zsh <= 5.3

[Sebastian Gniazdowski]

On 2 Jan 2018 at 17:57:26, dana (dana@dana.is) wrote:
> If the problem is ZSH_ARGZERO, shouldn't this work in like 5.0+?
> 
> () {
> setopt local_options posix_argzero
> MY_ARGZERO=$0
> }

I should be able to use this, by running it in plugin manager, and setting ZSH_BINARY or ZSH_BIN_PATH, so that this var can then be used in substitution, thanks. Although overall rather bad news, because plugins like z-sy-h can be just sourced. Someone with source-only setup (no p-m) could run such snippet himself, though. Kinda hard that Zsh doesn't set this information.

-- 
Sebastian Gniazdowski
psprint /at/ zdharma.org