Mmmm I believe what you shared Shai is very sophisticated than what is proposed. The proposal is a shortcut function for with ability to have a custom parent for more usability for an everyday use , like what's in the documentation about managers.
My proposal is *not* a new way to write managers . This can be your or someone else's fully baked idea. With respect. On Sun, 1 Jan 2023, 19:00 Shai Berger, <s...@platonix.com> wrote: > On Sun, 1 Jan 2023 16:33:45 +0200 > Ramez Ashraf <ramezash...@gmail.com> wrote: > > > > > Interested or do you think the function can be enhanced it to make > > more useable for your everyday other cases ? > > > > This is half-baked, just a thought, but maybe you can take it some > place interesting: > > Imagine a class that "collects" calls for later execution. Something > like (this exactly won't work, details below): > > from functools import partialmethod > from django.db.models import QuerySet as QSet > > class QS: > def __init__(self): > self._calls = [] > def filter(self, *args, **kw): > self._calls.append( > partialmethod(QSet.filter, *args, **kw) > ) > return self > def annotate(*args, **kw): > # ... (same idea) > # ... other relevant methods, > def __call__(self, qset): > for call in self._calls: > qset = apply(call, qset) > return qset > > This won't work, I think, because partialmethod isn't supposed to work > quite this way, and the "apply" in the last line isn't defined. But > with this (fixed) already you could, I think, do something like > > def qset_manager(qs: QS) -> Manager > class CustomManager(models.Manager): > def get_queryset(self): > orig = super().get_queryset() > return qs(orig) > return CustomManager() > > And then, in your model, > > class Person(models.Model): > ... > authors = qset_manager(QS().filter(role="A")) > > and now the "make a manager with a modified queryset" pattern is > shortened in a general way. > > As I said, just a half-baked thought. There's problems here to solve, > and many improvements to make. > > HTH, > Shai. > -- You received this message because you are subscribed to the Google Groups "Django developers (Contributions to Django itself)" group. To unsubscribe from this group and stop receiving emails from it, send an email to django-developers+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/django-developers/CAPtjUtg6JGLbdkcdTep-XbLVnogKg2EdJr%3DUJxP3Y0KRgmiaUA%40mail.gmail.com.
