object.enable() anti-pattern

[Steven D'Aprano]

On Thu, 09 May 2013 06:08:25 -0500, Wayne Werner wrote:

> Ah, that's it - the problem is that it introduces /Temporal Coupling/ to
> one's code: http://blog.ploeh.dk/2011/05/24/DesignSmellTemporalCoupling/

Good catch!

That's not the blog post I read, but that's the same concept. "Temporal 
Coupling" -- yes, that is an excellent description of the problem.


> You don't ever want a class that has functions that need to be called in
> a certain order to *not* crash. That's fine if you have to call them in
> a certain sequence in order to get the correct data - that's what
> programming is all about, after all. But if you provide me a class with
> a constructor you better make sure that when I do this:
> 
>      thing = YourSuperAwesomeClass()
>      thing.do_stuff()
> 
> that I don't get some horrid stack trace ending with
> 
>      InvalidStateError: initialize() needs to be called before
>      do_stuff()
> 
> Or something worse.

Exactly.


Thank you Wayne, that's a great help.



-- 
Steven