After researching, I found that the Nestjs documentation does not include any information about mixins. Here is what I have gathered from my findings on Google and Stack Overflow:
- A mixin serves as a means of code sharing between classes within Nest.
- Essentially, it is a class that contains methods that can be utilized by other classes, and can be declared as a provider with the
@Injectable()decorator. - Mixins enable the addition of extra functionalities to a class without altering the original class itself, and can be applied to controllers, services, pipes, and guards.
- Commonly, examples involve classes inheriting traits from mixins:
class SomeClass extends MixinClass {}
Initially, it appeared to me that this distinction was merely semantic, since inheritance implies a specific relationship between two classes, whereas a mixin is focused on code sharing. However, in practice, using a mixin in Nest seems to still rely on inheritance (utilizing the extends keyword).
My question now is: What exactly sets mixins apart? How do they differentiate from inheritance?
It appears that utilizing
class SomeClass extends SomeOtherClassThatIsntAMixin {}