> I am learning Python and relating to my knowledge of Java... What is > (Is there?) the equivalent of Java interfaces in Python? How could > I write my own?
There is no direct equivalent. Interfaces are implicit in Python, they are only really necessary in statically typed languages. Dynamically typed languages rely on "Duck typing" and therefore the concept of an interface is not required. ( Interfaces are a serious impediment to good OO design IMHO, they imply an element of fore knowledge of how a class will be used and involve additional work that often is not needed. They are basically a flexibility point introduced to mitigate against change in a static typing environment) A good example of duck typing is the concept of a "file like object" which is used in several places in Python. It basically means any object which has the same message protocol as a file. This is the saqme style of OOP used in SmallTalk, Lisp and ObjectiveC (although the latter also supports statically typed interfaces too) [ It is possible to create abstract classes in Python however using some sneaky tricks but the easiest way is probably just to throw an exception in the init method! Abstract classes are an alternative way to view interfaces - interaces are cut-down abstract classes...] Alan Gauld Author of the Learn to Program web site http://www.freenetpages.co.uk/hp/alan.gauld _______________________________________________ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
