[Edu-sig] Refocusing on Capabilities (was PySqueak)

[kirby urner]

On 5/26/06, Ian Bicking <ianb at colorstudy.com> wrote:

>
> Inheritance as an abstraction used for communication.  In other words,
> giving someone a class and telling them to subclass it.  Also, paying
> attention to the class hierarchy when consuming objects is discouraged.
>   Actually, paying any attention to the class when consuming an object
> is discouraged.
>

Several important standard library modules give you the classes to
inherit from, and invite you to write your own methods.  HTML and XML
parsing for example.

I don't see where Python discourages subclassing.

Then I think you're talking about duck typing, i.e. if it behaves a
certain way, it's OK to pass, and the type checking police won't be
strict about it, like in Java.  That I understand.  However, I
wouldn't call that discouraging -- I find it encouraging myself.  Too
much type checking is a pain, and is what discourages Java use.

Kirby