On 5/18/10, Dave Angel <da...@ieee.org> wrote: > Alex Hall wrote: >> Okay, that makes sense. So by calling submarine(craft) I am bringing >> in all of craft's attribs (subclassing)? Or does calling craft's >> __init__ method do that instead? Is there an advantage to doing it >> this way, rather than just making separate classes for everything, >> except for my own sense of organization; speed, memory usage, less >> coding? Thanks. >> >> <snip> >>> > You put your response at the wrong end of the message. It should > *follow* whatever you're quoting. So in your case, I'm forced to delete > everything just to make the order correct. Sorry, top-posting is a habit on some other lists I am on, and sometimes it follows me to lists where in-line posting is the way to do it. > > You don't call Submarine(Craft), as it's not a function. That's a class > definition. You instantiate a Submarine by something like: > > sub = Submarine(arg1, arg2, arg3) > > And those three arguments are then passed to the __init__() method of > Submarine. It may choose to call the __init__() method of Craft, in the > method. So that is the only way of making submarine inherit craft, by calling craft's __init__ inside submarine's __init__. Okay, I think I get it. > > There are lots of advantages of using inheritance. First, any common > code only has to be entered once, so you'll only have to fix it once > when you find mistakes, or decide to redesign. Very true. > Second, it's easier to > read - very important. It may take less memory, but probably not. And > it's not likely to have any speed impact. > > Craft instances don't have any instance data attributes if nobody > assigns them. And that's normally the job of __init__(). So naturally, > you need to call it from the Submarine class. Right, I think I have it now... At least I hope I do! > > Incidentally, convention is to capitalize class names. Yes, I had planned on doing that in my project, but I got caught up in just making it work and forgot to do so. Thanks for the reminder. > > DaveA > >
-- Have a great day, Alex (msg sent from GMail website) mehg...@gmail.com; http://www.facebook.com/mehgcap -- http://mail.python.org/mailman/listinfo/python-list
