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Monadic functional languages have native support for dependency injection and typeclasses/interfaces provide interoperability and easy mocking or alternative implementations with type-checking / propagation of which dependency they are using. (As to avoid mismatching between mocks and a real implementation for example)

https://itnext.io/hmock-first-rate-mocks-in-haskell-e59d7c3b...

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This article is just about mocks and doesn't really touch on dependency injection at all, and Haskell simply doesn't have the mechanisms to supply the kind of implicit passing that useful DI requires.

Sounds like you are taking about ReaderT, which is a common way of implicitly passing more data to functions. There are many other ways, though.

`Reader` and `ReaderT` are not implicit at all, they still need to pass parameters explicitly.

What other ways do you have in mind?

I am not aware of any Haskell functionality or compiler flag that enables implicit parameter passing, like Java, Kotlin, and Rust allow.

https://ghc.gitlab.haskell.org/ghc/doc/users_guide/exts/impl...

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