Python exceptions and refcounts

[Kragen Sitaker]

Duncan Booth <duncan at NOSPAMrcp.co.uk> writes:
> If you need to be sure that references to an object are removed even if the 
> function throws an exception then wrap the body of the function in a 
> try:finally: block and del the object in the finally suite. Also remember 
> always to close things like files and not depend on the variable going out 
> of scope to do the tidying up.

And, by the way, try:finally: is an excellent way to do things like
close files.

Lately I've been doing this kind of thing; instead of writing:

def getnext(self):
    tmp = self.seq[self.ii]
    self.ii = self.ii + 1
    return tmp

I do this:
def getnext(self):
    try: return self.seq[self.ii]
    finally: self.ii = self.ii + 1

In the absence of exceptions, both will do the same thing.

I'm not sure this is an actual improvement; I think I may be
succumbing to the Premature Optimization Demon, in its worst form: the
tendency to shorten one's code.