try...except...finally problem in Python 2.5

[Larry Bates]

redawgts wrote:
> I keep getting this error "local variable 'f' referenced before
> assignment" in the finally block when I run the following code.
> 
>         try:
>             f = file(self.filename, 'rb')
>             f.seek(DATA_OFFSET)
>             self.__data = f.read(DATA_SIZE)
>             self.isDataLoaded = True
>         except:
>             self.isDataLoaded = False
>         finally:
>             f.close()
> 
> Can someone tell me what's wrong with the code? Am I doing something
> wrong? I'm somewhat new to python but this makes sense to me.
> 
finally: block is executed even if there is an exception in which case f
hasn't been defined.  What you want is:

try:
    f = file(self.filename, 'rb')
    f.seek(DATA_OFFSET)
    self.__data = f.read(DATA_SIZE)
    self.isDataLoaded = True

except:
    isDataLoaded=False

else:
    f.close()

-Larry