[Distutils] some questions about PEP470

[holger krekel]

Hi Donald, Nick,

to change the somewhat unsuccessfull way how we were conversing about PEP470
so far i'd like to kindly ask you a few questions related to the PEP. 
This is to check if i am maybe barking up the wrong tree and also to
enlarge the common ground/understanding that we are discussing on.

Please take your time, i'd appreciate if you give a joint
answer rather than a quick one.

thanks,
holger


Numbers of users affected
---------------------------------

Do i see it right that the PEP470 changes would mean about 6-7 thousand 
users (per day) need to change their installation options to use
"--extra-index-url"?  If not, how many?  Is there a monthly figure?

And that the affected users can only do that if the respective
maintainers of the projects offer an external index (or re-upload to PyPI)?

Do i see it right that up to a 1000 maintainers need to act and offer an
external index if they want to keep their projects properly installable?

What can users of (older or current) easy_install versions do if they
want to install a project with external links in a post PEP470 world?

How many people currently use easy_install/not-pip (numbers, not only
percentages)?

I've understood you made these two statements during the discussion:

- PEP438 caused bad UI for dealing with pypi-external links -- 
  many people are confused by it and we thus need to fix it.
    
- PEP470 breaking backward compatibility for pypi-external links is
  not a big deal because it affects only a tiny fraction of the users.

Could you choose which one of them you consider is true?


Recommendation of "--extra-index-url"
--------------------------------------

In your mind and forgetting about PEP470, in what situations exactly is
"pip install --extra-index-url" a safe option for users?


Interpretation of external link usage
--------------------------------------------

In the main rationale you say:

    "While a large number of projects did ultimately decide to upload to
    PyPI, some of them did so only because the UX around what PEP 438 was so
    bad that they felt forced to do so."

Could you provide some tractable background (not just your strong opinion)
for this interpretation?  Why can it not be that people nowadays just
prefer to upload to PyPI without even considering alternative options?