Ron Ron - 4 days ago 5
Python Question

Django Many-to-Many (m2m) Relation to same model

I'd like to create a many-to-many relationship from and to a user class object.

I have something like this:

class MyUser(models.Model):
...
blocked_users = models.ManyToManyField(MyUser, blank=True, null=True)


The question is if I can use the class reference inside itself. Or do I have to use
"self"
insead of
"MyUser"
in the
ManyToManyField
? Or is there another (and better) way to do it?

Answer

Technically, I'm pretty sure "MyUser" or "self" will work, as long as it's a string in either case. You just can't pass MyUser, the actual class.

However, the docs always use "self". Using "self" is not only more explicit about what's actually happening, but it's impervious to class name changes. For example, if you later changed MyUser to SomethingElse, you would then need to update any reference to "MyUser" as well. The problem is that since it's a string, your IDE will not alert you to the error, so there's a greater chance of your missing it. Using "self" will work no matter what the class' name is now or in the future.

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