On Oct 30, 9:21 pm, "John [H2O]" <[EMAIL PROTECTED]> wrote:
> I would like to write a function to write variables to a file and modify a
> few 'counters'. This is to replace multiple instances of identical code in a
> module I am writing.
>
> This is my approach:
>
> def write_vars(D):
> """ pass D=locals() to this function... """
> for key in D.keys():
> exec("%s = %s" % (key,D[key]))
>
> outfile.write(...)
> numcount += 1
> do this, do that...
>
> the issue is that at the end, I want to return outfile, numcount, etc... but
> I would prefer to not return them explicitly, that is, I would just like
> that the modified values are reflected in the script. How do I do this?
> Using global? But that seems a bit dangerous since I am using exec.
>
> Bringing up another matter... is there a better way to do this that doesn't
> use exec?
What you're trying to do is hard to achieve but there's a reason for
that: it's a bad idea as it makes code really difficult to maintain.
You may want to define a class to contain all those variables that
need to be changed together:
class MyVars(object):
def __init__(self, outfile, numcount, ...):
self.outfile = outfile
self.numcount = numcount
def write_and_do_stuff(self):
self.outfile.write(...)
self.numcount += 1
# do this, do that...
Then you can use this in your functions:
def myfunction():
vars = MyVars(open('my.log', w), 0, ...)
# Do some stuff
vars.write_and_do_stuff()
# Do more stuff
You may even consider making some of those functions into methods of
the class.
--
Arnaud
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