From: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Date: Wed, 01 Feb 2012 21:25:31 GMT
Subject: Re: General support for ! in git-config values
Message-ID: <CACBZZX5mX55Rh8b2GYv7wKbCCypCkrn5AiM9BpXydgcYxHWdQA@mail.gmail.com>
In-Reply-To: <20120201184020.GA29374@sigill.intra.peff.net>

On Wed, Feb 1, 2012 at 19:40, Jeff King <peff@peff.net> wrote:
> On Wed, Feb 01, 2012 at 06:33:47PM +0100, Ævar Arnfjörð Bjarmason wrote:
>
>> For a program I'm working on (git-deploy) I'd like to have this as a
>> general facility, i.e. users can specify either:
>>
>>     foo.bar = value
>>
>> Or:
>>
>>     foo.bar = !cat /some/path
>>
>> I'm wondering why git-config doesn't do this already, if there's no
>> reason in particular I can just patch it in, either as a new option:
>>
>>     git config --with-exec --get foo.bar
>
> I'm not clear on what you want --with-exec to do. By default, config
> values are strings. I would expect the "!" to be a special marker that
> the caller would recognize in the string, and then act appropriately.
>
> So if I were implementing git aliases in the shell, the code would look
> like:
>
>  v=$(git config alias.$alias)
>  case "$v" in
>  "")
>          die "no such alias: $alias" ;;
>  "!*)
>          cmd="${v#!}" ;;
>  *)
>          cmd="git $v" ;;
>  esac
>  eval "$cmd"
>
> I.e., everything pertaining to "!" happens after we get the config
> string. So what is it that you want "git config --with-exec" to do?

I agree that that's how it should work, I just suggested --with-exec
in case anyone complained about the backwards compatibility issue of
changing the meaning of "!" for existing configs.