[Python-ideas] Add __parent__ to all classes, functions, and modules

[Benjamin Peterson]

Neil Girdhar <mistersheik at ...> writes:

> 
> 
> 
> On Sun, Oct 5, 2014 at 2:09 PM, Benjamin Peterson <benjamin <at>
python.org> wrote:
> Neil Girdhar <mistersheik <at> ...> writes:
> >
> > Many classes, functions, and modules are defined within the context of
> another class, function, or module thereby forming a mathematical forest of
> declarations.  It is possible to walk the descendants using __dict__ (for
> classes and modules), but not the ancestors.  I propose adding __parent__
> that would be filled at the same time that __qualname__ is filled in.This
is unlikely to work.
> 1) It turns basically everything into a cycle.
> 
> 
> Why a cycle? 

Because, for example, the class would reference methods, which would
reference the class.

> 
> 
> 2) __qualname__ is determined strictly from syntax, whereas __parent__ could
> not be. For example, what happens if I take a method from one class and set
> it on another? __parent__ would not be well-defined.
> 
> 
> I'm suggesting that parent be determined purely from declaration.  If you
copy something, neither qualname nor parent would change unless you change
them. 

It would mean your trick with super would only work for some methods.