os.path.basename works with URLs, why?

Question

>>> os.path.basename('http://example.com/file.txt')
'file.txt'

.. and I thought os.path.* work only on local paths and not URLs? Note that the above example was run on Windows too .. with similar result.

Answer 1

In practice many functions of os.path are just string manipulation functions (which just happen to be especially handy for path manipulation) -- and since that's innocuous and occasionally handy, while formally speaking "incorrect", I doubt this will change anytime soon -- for more details, use the following simple one-liner at a shell/command prompt:

$ python -c"import sys; import StringIO; x = StringIO.StringIO(); sys.stdout = x; import this; sys.stdout = sys.__stdout__; print x.getvalue().splitlines()[10][9:]"

Or, for Python 3:

$ python -c"import sys; import io; x = io.StringIO(); sys.stdout = x; import this; sys.stdout = sys.__stdout__; print(x.getvalue().splitlines()[10][9:])"

Answer 2

On windows, look at the source code: C:\Python25\Lib\ntpath.py

def basename(p):
    """Returns the final component of a pathname"""
    return split(p)[1]

os.path.split (in the same file) just split "\" (and sth. else)