for in sequence problem... possible new operator to add to python

[Greg Fortune]

See http://python.org/doc/current/ref/sequence-types.html to make your
objects happy little lists.

Greg


Adam Gent wrote:

> I was fooling around subclassing a dictionary object and noticed that
> when
> I do the standard "for in <object-is-a-sequence>:" that I have no
> control on how python gets that sequence.
> 
> For example:
> 
> class Blah(dict):
>    pass
> 
> bl = Blah()
> 
> for b in bl:
>     #b will be a key and not a value
>     #no matter how I subclass Blah
> 
> However I want b to be the values with out doing:
> for b in bl.values()
> 
> I could be wrong on this but I believe python is missing an operator
> for looping over objects. I think there should be a __sequence__ or
> __forsequence__ operator that returns a sequence when "for x in
> object" syntax is used.
> So
> for b in bl: == for b in bl.__sequence__