[Python-Dev] PEP 420 - dynamic path computation is missing rationale

[Eric V. Smith]

On 05/22/2012 11:39 AM, Nick Coghlan wrote:
> On Wed, May 23, 2012 at 12:51 AM, Eric V. Smith <eric at trueblade.com> wrote:
>> That seems like a pretty convincing example to me.
>>
>> Personally I'm +1 on putting dynamic computation into the PEP, at least
>> for top-level namespace packages, and probably for all namespace packages.
> 
> Same here, but Guido's right that the rationale (and example) should
> be clearer in the PEP itself if the feature is to be retained.

Completely agreed. I'll work on it.

> Oops, I also meant to say that it's probably worth at least issuing
> ImportWarning if a new portion with an __init__.py gets added - it's
> going to block all future dynamic updates of that namespace package.

Right. That's on my list of things to clean up. It actually won't block
updates during this run of Python, though: once a namespace package,
always a namespace package. But if, on another run, that entry is on
sys.path, then yes, it will block all namespace package portions.

Eric.