[NeveHanter]

DI is not a pattern to provide the defaults but a pattern that allows you to separate dependency initialisation from your callable's responsibilities, which often is a complex graph of inner dependencies that you would need to provide/initialise in some way, it also can handle whether you want to have single instance of such dependency for your single call, request scope, thread scope or process scope. Also injecting some defaults from configuration object or some properties/setting file is very nice feature.

Also stop being so religious and defensive when somebody mentions things that are not standard in your language of choice as nobody forces you to use this.

I was sucessfully building very testable and maintanable codebases (~50 kloc) in Python while also using very small in-house built DI framework and it was subjectively (by me and my collegues) much better than what we had before while we followed standard Python patterns and ways Python frameworks teach you to follow.

[jstx1]

What's the point of a DI framework? I never got the point of even thinking about DI explicitly like it's something special. It's so obvious that it hardly deserves to have a name, let alone a framework.

[rr808]

> (by me and my collegues)

Can I guess you were all Java developers?

[NeveHanter]

No, around 6-7 Python developers including me, we've used it in two different projects. Also it's probably worth mentioning that I'm not author of that lib, my die-hard anti Java collegue created it by just reading about DI, consulting with other collegue that was using Spring more-or-less since high school and researching existing DI libraries. I myself did some programming in Java before that, but it was mainly hobbist gamedev, later commercial Android and light Java backend work using Spring (that's where I've seen it used for first time) intermixed with around 7 years of professional Python backend programming in two different companies. Now after 10 years I'm an Java engineer, I've had enough of using dynamic languages to write moderately complex web applications.

I still love using Python for REPL, small scripts or prototyping, and I think having things like mypy is great as it takes away much of the burden without being a huge obstacle in some situations where you really need to use duck typing. Also I'm thankful that it teached me early that the debugger is one of the developer's best friends and the best documentation is just reading the code.