Gabriel Rossetti a écrit :
Hello everyone,

I'm trying to import some modules into another's namespace (network_utils)

network_utils.py:

import utils
import constants as main_const
from services import constants as srv_const
from plugins import constants as plg_const

#
# Import all the message creation functions
#
f = dict([ (f, eval("utils." + f)) for f in dir(utils) if f.startswith("create") ])

As usual, you don't need eval here. Use getattr instead:

create_functions = dict(
   (name, getattr(utils, name)
   for name in dir(utils)
   if name.startswith('create')
   )

__builtins__.update(f)


Python 2.5.1 (r251:54863, Apr  6 2008, 17:20:35)
[GCC 4.1.2 (Gentoo 4.1.2 p1.0.2)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> __builtins__
<module '__builtin__' (built-in)>
>>> type(__builtins__)
<type 'module'>
>>> __builtins__.update
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'module' object has no attribute 'update'
>>>

Anyway, adding to builtins is certainly not the best thing to do. I don't know what you're trying to do here, but looks like a very ugly mess to me.

del utils

#
# Create a virgin namespace
#
class constants:
   """
   An aggragation of L{constants},
   L{services.constants}, &
   L{plugins.constants}
   """
   pass


#
# Import all the constants into the new namespace
#
f = dict([ (f, eval("main_const." + f)) for f in dir(main_const) if f.isupper() ])
constants.__dict__.update(f)
del main_const
f = dict([ (f, eval("srv_const." + f)) for f in dir(srv_const) if f.isupper() ])
constants.__dict__.update(f)
del srv_const
f = dict([ (f, eval("plg_const." + f)) for f in dir(plg_const) if f.isupper() ])
constants.__dict__.update(f)
del plg_const

Yuck.

In your constants.py file, just add the relevant imports:

  from services.constants import *
  from plugins.constants import *

And then in your network_utils file:

  import constants

But this is still a mess to me. The nice point with explicit import and modules namespaces is that you at least have a chance to know where a given symbol comes from.


now, if I import network_utils somewhere, and try to call network_utils.myFunction() I get :

 >>> import network_utils
 >>> network_utils.myFunction
Traceback (most recent call last):
 File "<console>", line 1, in <module>
AttributeError: 'module' object has no attribute 'myFunction'

And ? Where is the name myFunction bound in the above code ?

but if I try to access the constants class:

 >>> from network_utils import constants
 >>> constants.NO_DATA_TYPE
'none'

it works, how come?

I suppose NO_DATA_TYPE is defined somewhere in one of your constants.py files.

Instead of messing with eval and builtins and wonder why something "works" and why something else doesn't, I strongly suggest you (re)read the part about imports, packages, modules etc in the FineManual.
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