Subject: Re: [boost] Environment Variables Library?
From: Andrey Semashev (andrey.semashev_at_[hidden])
Date: 2015-05-22 04:07:34
On Friday 22 May 2015 14:52:30 Gavin Lambert wrote:
>
> Also note that for the environment variables that do contain
> multi-paths, there are two separate delimiters in play -- one is the
> separator between entire paths, and the other is the separator between
> components of a single path. Both of them are platform-specific.
>
> It seems reasonable (though not essential) for an Environment library to
> take care of the former for you by providing split/rejoin methods that
> hide the difference between platforms.
+1
> It seems out of scope for it to do the latter, as this is already
> handled by the Filesystem library, and duplicating it seems wasteful.
>
> Hence the suggestion to have Environment provide split/join methods that
> use Filesystem path objects as a basis (ie. vector<path>), as this
> allows the most platform abstraction. And as others have already
> pointed out, Filesystem has been standardised already.
Note that not only paths can be present in multi-element env. variables. For
example, LS_COLORS contains a list of color specifications for ls command. I
think, it's better for the environment library to perform a split to a
sequence of strings and let the user interpret those strings as filesystem
paths or something else.