[Python-ideas] Quick idea: defining variables from functions that take the variable name

[Michael Selik]

On Wed, Jun 1, 2016 at 12:12 PM Michael Selik <michael.selik at gmail.com>
wrote:

> On Wed, Jun 1, 2016 at 9:23 AM Sven R. Kunze <srkunze at mail.de> wrote:
>
>> On 01.06.2016 08:25, Sjoerd Job Postmus wrote:
>> >> On 31 May 2016, at 16:37, Sven R. Kunze <srkunze at mail.de> wrote:
>> >>
>> >> Btw. there would be huge use-case for Django development. So, given
>> your explanation, it sounds useful.
>> > Could you elaborate on that use-case, because I'm not seeing it. I
>> think maybe you mean the ORM and declarative forms, correct?
>>
>> Exactly. That is one reason why Django needs metaclasses all over the
>> place. Because fields just don't know their name.
>>
>> This is especially true for forms as django does not magic there. It
>> always causes headaches if you need it.
>>
>
> Are you referring to code like this [0]?
>     your_name = forms.CharField(label='Your name')
>
> If so, I don't think we actually want the LHS to get passed in as the
> label. Not all labels will be valid identifiers. If you're talking about
> the CharField knowing what attribute it has been assigned to, I couldn't
> find that code in the Django source. Could you point it out?
>

I tracked it down
https://github.com/django/django/blob/master/django/forms/forms.py

BaseForm looks like a Mixin that needs the subclass to implement the
collection of the base_fields class attribute. Form uses the
DeclarativeFieldsMetaclass to inspect the constructed attributes and
capture the appropriate ones as base_fields.

I don't see how that would be improved by a special syntax for the LHS to
know the identifier it's being assigned to. Could you clarify that?
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