[IPython-dev] traitlets question [from Re: msg spec]

[Fernando Perez]

Hey Satra,

sorry for the delayed reply...

On Tue, Apr 17, 2012 at 7:27 PM, Satrajit Ghosh <satra at mit.edu> wrote:
>
>> > I've been using traitlets to do the message validation, and I'm running
>> > into
>> > the fact that we are unclear about what keys can be None and what
>> > cannot.
>> >  Should I start with the assumption that *anything* can be None, or not?
>>
>> I think that's a reasonable starting point. Once the tests are in
>> solid shape we can revisit this and go over the spec/implementation
>> more carefully.
>
>
> question out of not following the traitlets code. a long while back it was
> deemed that traitlets needed to have every element defined. is that no
> longer necessary? i.e could a trait be undefined (or set to None).

Dunno, sorry.  Brian?

> and to follow up, does traitlets have event delegation?

They have basic static and dynamic _foo_changed and on_trait_change
event handler like enthought.Traits do, but I think that Traits
support a more complex delegation pattern that we don't.

Brian or Robert will correct me if the above is mistaken...

Cheers,

f