At 03:21 PM 2/12/2005, Brian van den Broek wrote: [snip] > I am curious about Bob's "Whenever you find yourself writing > an if statement ask whether this would be better handled by subclasses."
class A: ... class A1(A); def foo(self, ...): statements to process object of type 1 class A2(A); def foo(self, ...): statements to process object of type 2
That takes less code. Eliminates the type property. I get greater visibility about the existence and distinction of the two (or more) sub-types. I now can much more easily extend each subtype.
Also you can more easily *add* a new subtype. Using if statements, if you add a new type you have to find all the relevant conditionals and add another condition. With subclassing, you create a new subclass and define the necessary methods. The changes are localized to the subclass and much easier to figure out.
Kent
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