En Sun, 24 Aug 2008 07:34:41 -0300, Mohamed Yousef <[EMAIL PROTECTED]> escribió:
> On Sun, Aug 24, 2008 at 9:59 AM, Fredrik Lundh <[EMAIL PROTECTED]> wrote: >> Mohamed Yousef wrote: >> >>> why am i doing this in the first place >>> I'm in the process of a medium project where imports of modules start >>> to make a jungle and i wanted all needed imports to be in a single >>> file (namely __init__.py) >>> and then all imports are made once and other modules feel it >> >> Python doesn't use a global namespace -- importing a given module into one >> module doesn't make it visible everywhere else (and trust me, this is a very >> good thing). > why isn't it a good thing (even if optional) > consider the sitution in which a utility module is used every where > else - other modules - > you may say import it in them all , Yes. That way, when you see a name "foo" used in a module, you can look at the imports to see where it comes from. (BTW, this is why using "from module import *" is not a good idea) Having a single global namespace is a lot worse. > what i changed it's name ? go back > change all imports... this doesn't seem good Yes. How often do you change the module's name? You may use an alias if you want to be backwards compatible. > and what about package wide varailbles ? If pkgA is a package, and you define a variable foo in its __init__.py, it is available as pkgA.foo - does it count as a "package wide variable"? >>> my goal is basically making W() aware of the re module when called >>> from A >> >> to do that, add "import re" to the top of the C module. > and sys ,string.. etc add them all twice or four / n times ? Every module has its own namespace, it contains its own set of imports, unrelated to others. If you want to use the re, or sys, or string modules - import them. As F.L. has already pointed, a module is loaded from disk only the first time it is imported; subsequent imports find the module in sys.modules and do nothing. > remove one and then forget to remove one of them in a file and start > debugging ... this really doesn't look to be a good practice Why is that? Importing an otherwise unused module is usually just a performance problem - at least for well-behaving modules that don't have side effects on import. -- Gabriel Genellina -- http://mail.python.org/mailman/listinfo/python-list
