Python's ABC's and Protocols are great. They are clean, simple, and straightforward.
But like all good things - they are not without faults.
Maybe your method names don't quite match the protocol; maybe you're using a 3rd party type and need to write an adapter; or maybe you want to extend your ABC, but your users already have a method with the same name!
What if you could simplify those edge-cases by baking-in the extra complexity?
Introducing - Explicit Interfaces!
Be explicit about the interfaces you implement, and create adapters with ease!
from explicit_interface import Interface, implements
class Duck(Interface):
def walk(self): ...
def talk(self): ...
@implements(Duck)
class Mallard:
@implements(Duck.walk)
def walk(self):
print("Walks like a duck")
@implements(Duck.talk)
def talk(self):
print("Talks like a duck")
class Human:
def walk(self):
print("Walks like a human")
def talk(self):
print("Talks like a human")
def interact_with_duck(duck: Duck):
duck = Duck(duck) # Adapt the duck
duck.walk()
duck.talk()
mallard = Mallard()
interact_with_duck(mallard) # Walks like a duck
# Talks like a duck
human = Human()
interact_with_duck(human) # TypeError
@implements(Duck, for_=Human)
class _:
@implements(Duck.walk)
def walk(self, human: Human):
return human.walk()
@implements(Duck.talk)
def talk(self, human: Human):
return human.talk()
interact_with_duck(human) # Walks like a human
# Talks like a humanuv add "explicit_interface @ git+https://github.com/tmr232/explicit-interface" 