making a valid file name...
python.list at tim.thechases.com
Tue Oct 17 19:14:10 CEST 2006
> Sometimes the user inputs characters that aren't valid
> characters for a file or directory name. Here are the
> characters that I consider to be valid characters...
> valid =
> ':./,^0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ '
Just a caveat, as colons and slashes can give grief on various
operating systems...combined with periods, it may be possible to
cause trouble too...
> This is what I have:
> def fixfilename(fname):
> valid =
> ':.\,^0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ '
> for i in range(len(fname)):
> if valid.find(fname[i]) < 0:
> fname[i] = ' '
> return fname
> Anyone think of a simpler solution?
I don't know if it's simpler, but you can use
>>> fname = "this is a test & it ain't expen$ive.py"
>>> ''.join(c in valid and c or ' ' for c in fname)
'this is a test it ain t expen ive.py'
It does use the "it's almost a ternary operator, but not quite"
method concurrently being discussed/lambasted in another thread.
Treat accordingly, with all that may entail. Should be good in
this case though.
If you're doing it on a time-critical basis, it might help to
make "valid" a set, which should have O(1) membership testing,
rather than using the "in" test with a string. I don't know how
well the find() method of a string performs in relationship to
"in" testing of a set. Test and see, if it's important.
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