A file iteration question/problem

[tinnews at isbd.co.uk]

Arnaud Delobelle <arnodel at googlemail.com> wrote:
> On Apr 6, 4:40 pm, tinn... at isbd.co.uk wrote:
> > I want to iterate through the lines of a file in a recursive function
> > so I can't use:-
> >
> >     f = open(listfile, 'r')
> >     for ln in f:
> >
> > because when the function calls itself it won't see any more lines in
> > the file.  E.g. more fully I want to do somthing like:-
> >
> > def recfun(f)
> >     while True:
> >         str = readline(f)
> >         if (str == "")
> >             break;
> >         #
> >         # do various tests
> >         #
> >         if <something>:
> >             recfun(f)
> >
> > Is there no more elegant way of doing this than that rather clumsy
> > "while True" followed by a test?
> >
> > --
> > Chris Green
> 
> You could use an iterator over the lines of the file:
> 
> def recfun(lines):
>     for line in lines:
>         # Do stuff
>         if condition:
>             recfun(lines)
> 
> lines = iter(open(filename))
> recfun(lines)
> 
Does that work though?  If you iterate through the file with the "for
line in lines:" in the first call of recfun(lines) you surely can't do
"for line in lines:" and get any sort of sensible result in recursive
calls of recfun(lines) can you?

-- 
Chris Green