ConfigParser & converting strings to lists

[JohnJacob]

"Chris Liechti" <cliechti at gmx.net> wrote in message
news:Xns9236975A47F67cliechtigmxnet at 62.2.16.82...
> "Edward K. Ream" <edream at tds.net> wrote in news:3D159F06.2154D3F3 at tds.net:
>
> > To complete this topic, let me restate the problem and JohnJacob's
> > elegant solution.
> >
> > Suppose files is a list of strings, and we have written a configuration
> > section like this:
> >
> >   config = ConfigParser.ConfigParser()
> >   config.set("recent files", "recentFiles, files)
> >
> > Then the elegant way of retrieving files _as a list_ is:
> >
> >   files = eval(config.get("recent files", "recentFiles"))
>
> it isn't that elegant i tend to call that sloppy ;-) the problem is that
> you execute arbitrary python expressions and you hope to get a list. but
> that is not sure, the user could have edited the config file.
> exec and eval are always a risk in your code. e.g they could rise any
> exception because you don't know what they realy execute.
>
> the split version is much more secure. you could also try a pickle. witch
> pickle.dumps you can get a string and reterive the old object using
loads()
> but that isn't as secure as split.
>
> if thats all too complicated, use your version with individual names
> "file1", "file2", ... it's much saver for a progrom that you release in
the
> wild.
>
> chris
>
> PS you mentioned you see double backslashes. maybe you looked at the repr
> of a string:
> >>> s = "he\tllo"
> >>> repr(s)
> "'he\\tllo'"
> >>> str(s)
> 'he\tllo'
> >>> print s
> he llo
> >>>
>
> as you can see there is not realy a double backslash...
>
> --
> Chris <cliechti at gmx.net>


Ugh! Not elegant? Seriously, though, Chris is right. I wouldn't distriute
code like that. It is dangerous in the security sense and in the stability
sense. For scripting your own system I wouldn't think that would be too big
of a problem.

If it's going to be distributed I would go with the split() method others
have suggested.


greg

P.S. Do you have an Erdos number? I've never talked to anyone who actually
has one (that I know of).