[Python-Dev] import problems (original) (raw)

Mart Somermaa mrts at mrts.pri.ee
Fri Nov 28 13:59:39 CET 2008

Nick Coghlan wrote:

As Hrvoje has pointed out, 'sys' is part of the internal interpreter machinery - it's there as soon as the interpreter starts. The import call for it just grabs it out of the module cache and creates a reference to it in the current namespace. I understand that, but

Explicit is better than implicit.

--> non-explicit import sys and import(modname) to access

 sys.modules[modname]

Simple is better than complex.

--> three lines for a common use case instead of one

Readability counts.

--> why is sys imported in this WSGI app (that shouldn't generally

 touch any of the common sys.argv, sys.stdout etc)?!

 (500 lines later) aha, to access sys.modules

There should be one-- and preferably only one --obvious way to do it.

--> should I use the 3-line idiom? should I use the getattr() idiom?

Ideally, __import__() should support the only obvious way.

In short, the three-line version doesn't convey the intent in an obvious way and does more work than is necessary.

More information about the Python-Dev mailing list