Re: [PATCH] Add support for HTTP proxies

[Taylan Ulrich B.]

address@hidden (Ludovic Courtès) writes:

> address@hidden (Taylan Ulrich B.) skribis:
>
>> address@hidden (Ludovic Courtès) writes:
>>
>>> What about just:
>>>
>>>   (make-parameter (getenv "http_proxy"))
>>
>> The empty-string case needs to be handled specially, no?
>
> Could be, but OTOH it’s a user error.
>
> Ludo’.

Hmm, I can easily imagine shell scripts and especially CLI users running
a command like

  http_proxy= my-command

(which --don't be fooled by shell syntax-- sets it to an empty string)
to disable the HTTP proxy for that command, expecting it to work (I too
would), because it's easier than to use the `unset' command (which would
require invoking a sub-shell, or saving and restoring the variable's
value, to not affect subsequent commands in the script or session).

I don't know if there's already scripts out there doing that (wouldn't
be surprised), or whether there's any authoritative specification of
what should happen in that case.  I see though that wget and curl both
support the empty string to mean "no proxy."

So I think we should support it.

(By the way there's also the option to just leave it as the empty string
but expect subsequent functions using the variable to handle the empty
string themselves, but I suspect that would be the wrong approach.)