* Kent Johnson <[EMAIL PROTECTED]> [051112 20:33]: > Tim Johnson wrote: > >I need to get up to speed on iterators. I learned python 1.5~ via > >Alan G's book ... > >For an example, I've written a subclass of dict where keys are kept in > >a ordered fashion is a list called __keys: > > > >#Here is my items function: > > def items(self): > > """ Return all pairs in order of addition""" > > return [(key,self.__dict[key]) for key in self.__keys] > > > >#And here is my iteritems function (currently does exactly the same thing) > > def iteritems(self): > > """ At this implementation, does exactly the same thing as > > method items()""" > > for key in self.__keys: > > yield (key,self.__dict[key]) Ah. I did it right without know what I was doing. Now if I assign a value to the iteritems method, as in it = s.iteritems() I get an object of <dictionary-iterator object at 0x407e3a40> and dir(it) shows that (it) has one public method - next().
Question: Can one subclass an iterator object? thanks for making this a little clearer. tim > I think you have it right. Your two methods don't do the same thing - > items() returns a list of key, value pairs; iteritems() returns a generator > which yields key, value pairs. This is the correct behaviour. > > Kent > -- > http://www.kentsjohnson.com -- Tim Johnson <[EMAIL PROTECTED]> http://www.alaska-internet-solutions.com _______________________________________________ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
