Jon Ribbens via Python-list schreef op 3/08/2021 om 17:48:
On 2021-08-03, Michael Torrie <torr...@gmail.com> wrote:
> On 8/2/21 1:43 PM, Sven R. Kunze wrote:
>> maybe, I am missing something here but is it possible to specify a
>> delimiter for list arguments in argparse:
>>
>> https://docs.python.org/3/library/argparse.html
>>
>> Usually, '--' is used to separate two lists (cf. git).
>
> I've not seen this syntax in git. Are you referring the the double and
> triple dot notation git uses? Can you give me an example of how git
> uses -- as a list separator?
Loads of git commands do this. e.g. commit, diff, log, status, etc.
It's not completely unlike what you're describing above, which is
already supported automatically by argparse.
Commands like git commit do not use '--' to separate two lists, but as
Dan and Sven said to separate options from arguments, even if the
arguments start with '-' (like many other programs -- I think this is
standard in GNU). If you're 100% certain that none of the filenames
start with '-', you can leave out '--' without any change in behavior.
Especially when scripting and/or using wildcards it's best always to use
that '--' to avoid nasty surprises.
$ git commit -m "hello" -- hello.py
is exactly the same as
$ git commit -m "hello" hello.py
It's just that the former is safer to use, because it properly works
even in cases like
$ git commit -m "hello" -- -hello.py
whereas
$ git commit -m "hello" -hello.py
will likely not do what you expect.
As https://git-scm.com/docs/git-commit says:
> --
> Do not interpret any more arguments as options.
--
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faster than society gathers wisdom."
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