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The importer stored in the cStringIO data structure and the physical disk file

Is there a way to import a Python module stored in a cStringIO data structure or a physical disk file?

It looks like "imp.load_compiled (name, pathname [, file])" is what I need, but the description of this method (and similar methods) has the following disclaimer:

Quote: "The file argument is a file of byte compiled code, open for reading in binary mode from the start. It must be a real file object, not a user-defined class that emulates the file." [1]

I tried using a cStringIO object against a real file object, but the reference documentation is correct - only the real file can be used.

Any ideas as to why these modules impose such a limitation or is it just a historical artifact?

Are there any methods I can use to avoid this physical file requirement?

Thanks, Malcolm

[1] http://docs.python.org/library/imp.html#imp.load_module

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Is something like this possible?

import types
import sys

src = """
def hello(who):
    print 'hello', who
"""

def module_from_text(modulename, src):
    if modulename in sys.modules:
        module = sys.modules[modulename]
    else:
        module = sys.modules[modulename] = types.ModuleType(modulename)
    exec compile(src, '<no-file>', 'exec') in module.__dict__
    return module

module_from_text('flup', src)
import flup
flup.hello('world')

What prints:



hello world

EDIT

Evaluating code this way moves closer to the realm of writing custom importers. It might be helpful to look at PEP 302 and Doug Hellmann PyMOTW: Modules and Imports .

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