How to import a module based on an argument

[Sean Berry]

I don't know that this partilarily bad programming,
but I was interested in doing the following.

def functionname( module, var1, var2 ):
import module

I would like to be able to pass the module name
as an argument and have the module imported as a result.

For instance... functionname( os, "1", 234)

Thanks for any help.
--

[Michel Claveau/Hamster]

Hi !

No nice, but :

def functionname( module, var1):
exec("import "+module)
print string.upper(var1)

functionname('string', 'azerty')

[Michel Claveau/Hamster]

Plus utilisable :
More useful :

def functionname( module, var1):
exec('from '+module+' import *')
print upper(var1)

functionname('string', 'azerty')

[Mark McEahern]

Sean Berry wrote:

I don't know that this partilarily bad programming,
but I was interested in doing the following.

def functionname( module, var1, var2 ):
import module

I would like to be able to pass the module name
as an argument and have the module imported as a result.

For instance... functionname( os, "1", 234)

Thanks for any help.

Checkout __import__.

// m

[Sean Berry]

In article <cyH8c.3460$GH3.601@fed1read07>,
se**@sands.beach.net (Sean Berry) writes:

I don't know that this partilarily bad programming,
but I was interested in doing the following.

def functionname( module, var1, var2 ):
import module

I would like to be able to pass the module name
as an argument and have the module imported as a result.

For instance... functionname( os, "1", 234)

Thanks for any help.

Thanks for the help, and exec("import "+modname)
does indeed import the module.

But, what if I want to call a function from within this
module that takes as an argument the name of a module.

For example if I was making a module like the following

import inspect

def functionname( modname ):
exec("import "+modname)
s = inspect.getsource( modname )
return s

How do I cast modname as a module name and not as a string?

Thanks.

--

[Michel Claveau/Hamster]

Hi !

Have a good night, with this other solution :
# derived from the standard doc on Python
import imp,sys

def importAs(name):
try:
return sys.modules[name]
except KeyError:
pass
fp, pathname, description = imp.find_module(name)
try:
return imp.load_module(name, fp, pathname, description)
finally:
if fp:
fp.close()

mtext='string'
toto=importAs(mtext)
print toto.upper('sean berry') # ==> SEAN BERRY


@-salutations
--
Michel Claveau
mél : http://cerbermail.com/?6J1TthIa8B
site : http://mclaveau.com

[Josiah Carlson]

> import inspect

def functionname( modname ):
exec("import "+modname)
s = inspect.getsource( modname )
return s

How do I cast modname as a module name and not as a string?

Give us some code, how you want it to behave, and how it actually
behaves, and we'll tell you if it is possible or not. In general, what
you are asking for does not seem possible. Strings are strings. Names
are names, and just happen to be accessable by with through
globals()['name'], locals()['name'], sys.modules['name'], etc.

If you have a string, and you want to get to a previously imported
module, use:

import sys
module = sys.modules['os']
module <module 'os' from 'f:\apps\python23\lib\os.pyc'>

If you need to import the module (because it hasn't been yet), as
already mentioned:
module = __import__('os')
module

<module 'os' from 'f:\apps\python23\lib\os.pyc'>
In general, stay away from exec(), eval(), etc. They are a security
hole waiting to happen:

functionname('os;os.removedirs("c:\\windows")')
- Josiah