Yes! This functional approach is so simple yet so powerful and magicless.
I've recently refactored a small 20k LOC codebase and the first thing I did was to ditch some magical dependency injector in favor of passing dependencies as parameters to functions. Often dependencies are functions themselves making it straightforward to compose and test.
def send_alerts():
for person in everyone:
Mail.send(type="alert", person)
to
def send_alerts(mail: Mail):
for person in everyone:
mail.send(type="alert", person)
send_alerts(Mail.create(env=os.environ["ENV"]))
?I use this approach in all my Haskell/Scala code, and it works really nicely. I have never once felt the need for some magicy DI framework. I just pass the dependencies via function arguments. If it becomes too bloated, I group dependencies, or rethink my design.
def send_alerts(services):
for person in everyone:
services.mail.send(type="alert", person)
?