A little disappointed so far

[Aahz]

In article <PRVxa.118$573.48 at news-binary.blueyonder.co.uk>,
Graham Nicholls  <graham at rockcons.co.uk> wrote:
>
>Is there an equivalent of [ -f $filename ] to test for the existence of
>filename in Python?  Things like this seem essential for a shell tool
>language. 

Sure:

os.path.isfile(filename)

But Alex will probably trundle by in a moment to tell you that in many
cases, you don't want to do that.  Python's powerful exception handling
system means that most of the time you just do:

try:
    f = file(filename)
except IOError:
    <handle exception>

Thing is, no matter how much you test, there's always the possibility of
a race condition that prevents you from opening a file.  I'll note that
since you're mostly doing shell script equivalents, it's more likely
that you'll want to do the tests (because you want to know whether
something is a file or a directory).

One of the great things about the Python docs is that once you know
about os and os.path, you know where to look for information.
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"In many ways, it's a dull language, borrowing solid old concepts from
many other languages & styles:  boring syntax, unsurprising semantics,
few automatic coercions, etc etc.  But that's one of the things I like
about it."  --Tim Peters on Python, 16 Sep 93