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[Python-Dev] Dropping __init__.py requirement for subpackages

Clark C. Evans cce at clarkevans.com
Tue Jun 20 16:36:21 CEST 2006 
+1 Excellent Change
+1 Minimal Backward Compatibility Difficulties

I think this would also help quite a bit with newbie adoption of Python.
I've had to explain this un-feature on numerous occassions and it given
how smart Python is, I've wondered why it has this requirement.  If you 
look in various open source packages, you'll find that 95% of these
__init__.py files are empty.  The ones at my work actually say:

  # stupid Python requirement, don't remove this file

Why?  Someone decided to remove files of length 0 in our repository
without realizing the consequences.  Since it had the __init__.pyc file
around, it still worked... till one brought down a fresh copy of the 
repository and then it just "stopped" working.  Quite a bit of hair
pulling that one caused us.

The only case where this might cause a problem is with "resource"
directories that only contain ".html", ".jpg" and other files.  So,
perhpas this feature would only turn a directory into a package if
it didn't have any .py files.  It could also trigger only when the
package is explicitly imported?

Good luck /w the pitch-fork wielding users and telling the old-timers
where they can keep their backward compatibility.

Clark
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