design question: no new attributes

[Gabriel Genellina]

En Wed, 28 Feb 2007 09:41:47 -0300, Alan Isaac <aisaac at american.edu>  
escribió:

> However I will observe that
> - entire languages are structured on the premise that dynamic
> attribute creation can be hazardous

That's why we have so many languages to choose from. What is highly  
important for someone is irrelevant for others. [PL/1 was destined to be  
The Programming Language...]
If you actually dislike the concept of dynamic attribute creation, you're  
using the wrong language.

> - debuggers watch out for dynamic attribute creation, which
> tells us it is a common source of bugs

Which debugger, please? Might be interesting. (As a debugging tool, not as  
a design technique).

> - I sincerely doubt that anyone who has written more than
> a couple scripts in Python has never accidentally created an
> attribute dynamically while intending to assign to an existing
> attribute.

That *might* happen, but not so frequently as to fight against the dynamic  
nature of Python.

> I know the response: write good unit tests.  OK, but right now
> I am writing code where this restriction will serve as a reasonable
> error check, and the design I offered allows very easy removal
> of the restriction in the future. Say, once I have written adequate
> unit tests.

If it suits your needs, fine! But you'll find that most Python programmers  
won't agree with your approach.

-- 
Gabriel Genellina