I'm not sure what parts of FP python has you're referring to but it seems pretty lacking. It has a few combinators, that's about it.
The influence of "FP" on rust is really more like the influence of Haskell's type system. Rust is pretty far from a functional language but it does share a lot of type system features with Haskell: type classes, sum and product types, HM type inference
Rust not only has some good parts from FP; they are added thoughtfully enough to keep them logically sound. So the fact that there are math-backed theories behind them still matters.
With C++, I can't say the same is true. Some libraries try to alleviate that, of course.
Re:Idiomatic Monads in Rust
by rujuladanh on Thursday April 04, 2019 @08:26PM
(#19578483)
What math-backed theories? Why do they matter? Do you mean for the compiler team or for the users?
Hindley-Milner type inference and linear types (used indirectly for lifetimes) spring to mind.
Re:Idiomatic Monads in Rust
by rujuladanh on Saturday April 06, 2019 @04:04PM
(#19592712)
Those are useful for compiler devs and language designers, not so much for the average user of the language.
I think it is a matter of choice of audience. If you want pure functional languages, there are plenty that will rock your boat (Haskell, OCaml ...).
But, to my mind, I see Rust as a somewhat "modernised" C/C++ with, like Python, the most interesting and accessible parts of FP backed in. It is a balance and it is fragile. So, as I said, I hope that Rust will keep that fine line.
All that said, it only is my opinion, I might be wrong and the wider audience might be ready for "harder" FP. But I doubt it.