New PEP: Attribute Access Handlers

[Gordon McMillan]

Neel Krishnaswami wrote:

>Gordon McMillan <gmcm at hypernet.com> wrote:

[Paul's proposal creates one access handler per attribute...]

>I'm afraid I still don't understand. 

Oh, I think you do <wink>.

>If I wanted to use separate
>accessors/mutators, what would I do with the current proposal?

One possibility is to oppose it, though that's probably not necessary, 
since it's not yet coherent.

>An example (using separate accessors) that I'd like to see translated:
>
>class Foo:
>   def __init__(self, x):
>       self.x = x
>
>
>class LogWrites(Foo):
>   def __set_x__(self, x, val):
>       add_to_write_log()
>       self.__dict__['x'] = val 

The current proposal is to write

  def __attr_x__(self, op, val=None):
    if op == 'get':
       ...
    elif op == 'set':
       ...
    elif op == 'del':
       ...

IOW, in the current proposal, you can't.

- Gordon