[Python-checkins] r51203 - peps/trunk/pep-0302.txt
georg.brandl
python-checkins at python.org
Fri Aug 11 09:11:15 CEST 2006
Author: georg.brandl
Date: Fri Aug 11 09:11:14 2006
New Revision: 51203
Modified:
peps/trunk/pep-0302.txt
Log:
Add a sentence clarifying that once a path_hooks importer has
been found for a sys.path entry, the builtin import machinery will not
handle that entry any longer.
Modified: peps/trunk/pep-0302.txt
==============================================================================
--- peps/trunk/pep-0302.txt (original)
+++ peps/trunk/pep-0302.txt Fri Aug 11 09:11:14 2006
@@ -311,13 +311,16 @@
sequence to determine if they can handle a given path item. The
callable is called with one argument, the path item. The callable
must raise ImportError if it is unable to handle the path item, and
- return an importer object if it can handle the path item. The
- callable is typically the class of the import hook, and hence the
- class __init__ method is called. (This is also the reason why it
- should raise ImportError: an __init__ method can't return anything.
- This would be possible with a __new__ method in a new style class,
- but we don't want to require anything about how a hook is
- implemented.)
+ return an importer object if it can handle the path item. Note
+ that if the callable returns an importer object for a specific
+ sys.path entry, the builtin import machinery will not be invoked
+ to handle that entry any longer, even if the importer object later
+ fails to find a specific module. The callable is typically the
+ class of the import hook, and hence the class __init__ method is
+ called. (This is also the reason why it should raise ImportError:
+ an __init__ method can't return anything. This would be possible
+ with a __new__ method in a new style class, but we don't want to
+ require anything about how a hook is implemented.)
The results of path hook checks are cached in
sys.path_importer_cache, which is a dictionary mapping path entries
More information about the Python-checkins
mailing list