On 29 January 2014 11:41, Donald Stufft <donald@stufft.io> wrote:
On Jan 29, 2014, at 4:23 AM, Paul Moore <p.f.moore@gmail.com> wrote:
As I recall, it was in the original version of the PEP/spec and it was always an intended feature. The wheel file for the wheel project itself is (deliberately) runnable as a zip file, so that you can bootstrap into the wheel world using the "wheel install" command.
I just read every version of the PEP that has ever existed in Mercurial and no version besides Nick's most recent contains any text about the importability of Wheels besides that one of the differences of Wheel and Egg is that Wheel is an installation format and Egg is importable.
Apologies. It was something Daniel pointed out a few times very early on - I hadn't realised it wasn't in the spec directly. What is in the spec - which effectively constrains the format to *allowing* (rather than encouraging) direct import - are the facts that wheels are zip format, and that one of purelib/platlib is at the root. The concept of separating "unpack" and "spread" and the comment "Although a specialized installer is recommended, a wheel file may be installed by simply unpacking into site-packages" doesn't leave any room for wheels *not* to be importable in the majority of pure-python, no package data, cases. Debating how we present this in later versions of the wheel spec is fine. But deliberately making wheels not importable would break backward compatibility in a way that would have other, likely more serious, implications. Nevertheless, I understand your concerns, and I think we should be very careful not to let people get the impression that this is in any way similar to "importable eggs", which had a very bad press. Paul