[Python-Dev] making the import machinery explicit (original) (raw)

Brett Cannon brett at python.org
Tue Apr 17 20:01:18 CEST 2012

On Tue, Apr 17, 2012 at 13:45, Philip Jenvey <pjenvey at underboss.org> wrote:

On Apr 14, 2012, at 1:03 PM, Brett Cannon wrote: > And lastly, sticking None in sys.pathimportercache would no longer mean "do the implicit thing" and instead would mean the same as NullImporter does now (which also means import can put None into sys.pathimportercache instead of NullImporter): no finder is available for an entry on sys.path when None is found. Isn't it more explicit to cache the NullImporter instead of None?

I disagree. NullImporter is just another finder that just so happens to always fail. None is explicitly not a finder and thus obviously not going to do anything. Isn't it clearer to say sys.path_importer_cache[path] is None than isinstance(sys.path_importer_cache[path], imp.NullImporter)? I mean we have None to represent something is nothing which is exactly what I want to convey; None in sys.path_importer_cache means there is no finder for that path. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mail.python.org/pipermail/python-dev/attachments/20120417/6b10fd20/attachment.html>

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