Pass !, !=, ~, <, > as parameters

Question

I want to be able to pass arguments like this:

fn(a>=b) or fn(a!=b)

I saw this behavior in DjangoORM and SQLAlchemy but I don't know how to achieve it.

Answer 1

ORMs use special methods on classes for a and b to hook into operators and customise what is produced.

>= for is handled by the object.__ge__() method, while != calls object.__ne__().

Typically, the ORM object used for a returns a new object with the operation applied, allowing you to chain operations, and the fn() function expects such an ORM object and will read the operation status from there.