Comment by probabletrain

I think there’s a difference between what’s expected/acceptable for library code vs application code. Types like this might be hard to understand, but they create very pleasant APIs for library consumers. I’ve generally found it very rare that I’ve felt the need to reach for more complex types like this in application code, however.

RXJS’s pipe function has a pretty complex type for its signature, but as a user of the library it ‘just works’ in exactly the type-safe way I’d expect, without me having to understand the complexity of the type.