[Python-3000] PEP 3124 - Overloading, Generic Functions, Interfaces, etc. (original) (raw)

Phillip J. Eby pje at telecommunity.com
Wed May 9 18:34:02 CEST 2007

At 09:58 PM 5/8/2007 -0400, Chris Monson wrote:

If we are looking at doing Design By Contract using @before and @after (preconditions and postconditions), shouldn't there be some way of getting at the return value in functions decorated with @after?

Actually, it isn't really design by contract; i.e., I wasn't using the word "postconditions" in the DBC sense. I was saying you could put code there to ensure (i.e. implement) additional postconditions, not check them.

If you wanted to implement DBC, it might be simplest to subclass overloading.Around to create a Contract class and @contract decorator, with a higher method-combination precedence than Around methods. Indeed, that might make another nice example for the PEP.

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