Should documentation discuss how validators work together (and their ordering)?

[MimmyJau]

Context

I was going through the docs trying to understand if a custom field-level def validate_<field_name>(self, value): function (specified here in the docs) would override the default validators.

Example

While this example is a bit contrived, suppose I had a models.PositiveIntegerField field and wanted to set a maximum value on it (using a custom validator). Would I then have to re-validate that it was still a positive integer (something handled by the default validator)?

Suggestion

The docs could give a brief overview of how the multiple validators work in conjunction with one another (e.g. that custom validators don't override default validators but instead extend them). The best summary I could find so far was in the answers to this StackOverflow question (the top two in particular).

Moreover, should there be a high-level overview of the ordering of validation? i.e.

1. Default field-level validators
2. Field-level validators specified by the validators=[] parameter
3. Field-level validators specified by def validate_<field_name>:
4. Object-level validators specified by def validate(self, data):

I would offer to do this, but I'm not sure I even fully understand it myself yet. That being said, I'm happy to contribute where I can.