How to pass parameter when importing a module?

[Bo Peng]

Dear list,
What I would like to do is something like:
In myModule.py ( a wrapper module for different versions of the module),
  if lib == 'standard':
from myModule_std import *
  elsif lib == 'optimized'
from myModule_op import *
but I do not know how to pass variable lib to myModule.py to achieve the 
following effect:

   lib = 'standard'
   from myModule import * # actually import myModule_std
From what I have read, from  does not take any parameter. Maybe I 
should use environmental variables?

   os.putenv('lib', 'standard')
   from myModule import *
  myModule.py
  -
  import os
  lib = os.getenv('lib')
  ...
or use a separate module?
  param.py
  -
  para = {}
  def setParam(key, val):
para[key] = val
  main session
  
   import param
   param.setParam('lib','standard')
   from myModule import *
  in myModule.py
  --
  from param import para
  try:
lib = para['lib']
  except:
lib = 'standard'
  ...
Is there an established approach for this problem?
Many thanks in davance.
Bo
===
FULL STORY:
I have several modules all (SWIG) wrapped from the same C++ source code 
but with different compiling flags. For example,

  myModule_std  (standard module)
  myModule_op   (optimized, without error checking)
  ...
These modules are put directly under /.../site-packages . To load a 
module, I use, for example

  from myModule_op import *
This works fine until I need to write some helper functions for 
myModule_?? in another module myHelper.py since I do not know which 
myModule is being used

  from myModule?? import A,B
I find one solution
  # find out which module is being used
  import sys
  if 'myModule_op' in sys.modules.keys():
from myModule_op import A,B
  else:
from myModule_std import A,B
but not completely satisfied. Therefore, I am writing a 'wrapper' module 
myModule that can load one of the myModule_?? modules according to user 
supplied info.

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Re: How to pass parameter when importing a module?

[Swaroop C H]

On Sun, 20 Mar 2005 10:18:14 -0600, Bo Peng [EMAIL PROTECTED] wrote:
 What I would like to do is something like:
 In myModule.py ( a wrapper module for different versions of the module),
if lib == 'standard':
  from myModule_std import *
elsif lib == 'optimized'
  from myModule_op import *

Suggestion: Maybe you use builtin `__import__` to load a module ? Note
that in this way, you'll have to use the module name prefix.


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Blog: http://www.swaroopch.info
Book: http://www.byteofpython.info
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Re: How to pass parameter when importing a module?

[André Roberge]

Bo Peng wrote:
Dear list,
What I would like to do is something like:
In myModule.py ( a wrapper module for different versions of the module),
  if lib == 'standard':
from myModule_std import *
  elsif lib == 'optimized'
from myModule_op import *
but I do not know how to pass variable lib to myModule.py to achieve the 
following effect:

How about this:
#= constants.py
lib = whatever   #assigned somewhere else
#= myModule.py
from constants import lib
etc.
André
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Re: How to pass parameter when importing a module?

[Serge Orlov]

Bo Peng wrote:
 Dear list,

 What I would like to do is something like:

 In myModule.py ( a wrapper module for different versions of the
 module),
   if lib == 'standard':
 from myModule_std import *
   elsif lib == 'optimized'
 from myModule_op import *

 but I do not know how to pass variable lib to myModule.py to achieve
 the following effect:

lib = 'standard'
from myModule import * # actually import myModule_std

[snip]

Take a look at wxPython versioning:
http://wiki.wxpython.org/index.cgi/MultiVersionInstalls

The most simple usage looks like

  import wxversion
  wxversion.select(2.4)
  import wx
  Serge. 


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Re: How to pass parameter when importing a module?

[Bo Peng]

Take a look at wxPython versioning:
http://wiki.wxpython.org/index.cgi/MultiVersionInstalls
The most simple usage looks like
  import wxversion
  wxversion.select(2.4)
  import wx
  Serge. 

This is essentially my second method: using another module to set 
parameter for myModule. Since wxPython uses this method, I suppose this 
is the standard approach for this problem.

Thanks.
Bo
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