Gregor Horvath wrote:
> Hi,
>
> given the dynamic nature of python I assume that there is an elegant
> solution for my problem, but I did not manage to find it.
>
> I have a file that contains for example on line:
> ['147', '148', '146']
> when I read the file
> f = file("I050901.ids").readlines()
Y3K bug alert :-)
> I have a string
> f[0] == "['147', '148', '146']"
The last (or sole) line is highly likely to be "['147', '148',
'146']\n". If there are multiple lines in the file, all but the last
will definitely have "\n" at the end.
> How can I turn this string into a list
> li == ['147', '148', '146']
> without parsing?
Something like this:
>>> def munch(astrg):
... return [x[1:-1] for x in astrg.rstrip("\n")[1:-1].split(", ")]
...
>>> munch("['147', '148', '146']")
['147', '148', '146']
>>> munch("['147', '148', '146']\n")
['147', '148', '146']
>>> munch("['147']\n")
['147']
>>> # Warning: various flavours of "nothing" give the same result:
>>> munch("['']\n")
['']
>>> munch("[]\n")
['']
>>> munch("\n")
['']
>>>
This assumes that the contents are no more complicated than in your example.
Some notes:
(1) You neither want nor need to use eval.
(2) What is creating files like that? If it is a Python script, consider
writing them using the csv module; that way, other software can read
them easily.
HTH,
John
--
http://mail.python.org/mailman/listinfo/python-list
