How to query by concrete type from standard querysets?

[pbassut]

So, I have the following models:

class Task(PolymorphicModel):
    title = models.CharField(max_length=100)

class TaskTopic(Task):
    topic = models.ForeignKey(Topic, default=None, null=True)

class Event(models.Model):
    tasks = models.ManyToManyField(Task, db_table='event_tasks')

I wanna filter by the topic field. I tried something like this but it didn't work.

Event.objects.filter(tasks__instance_of=TaskTopic)

Any ideia of how to do this?

[vdboor]

This would suggest the filter won't be applied to the queryset of the m2m model.

You may want to try something like this as a workaround:

ct = ContentType.objects.get_for_model(TaskTopic)
Event.objects.filter(tasks__polymorphic_ctype=ct)