That's my point. I think people complaining that Rust (or Haskell, or whichever paradigm shift) "takes too long to learn" have forgotten what it was to learn their first language. It took them long, because some things take long. Learning something different takes time, but it's easy to forget this once you have a couple of languages under your belt.

> I think people complaining that Rust (or Haskell, or whichever paradigm shift) "takes too long to learn" have forgotten what it was to learn their first language

Because they are required to be productive fast. A professional usually doesn't learn a new language just for the sake of it. If the language doesn't yield instant benefits then most people aren't going to bother learning it.

If a steep learning curve is expected for rust then the language will never be popular around the people who could potentially make use of it, i.e. C or C++ developers.

C++ has a pretty steep learning curve, yet people use it.

Many things in tech are tradeoffs. Sometimes the additional tools a language brings to the table are worth the learning curve, sometimes they aren't. There are people in the industry for which FP (or Rust, or whatever) is worth it. For you it isn't. That's life.

> C++ has a pretty steep learning curve, yet people use it.

C++ has 30+ years of libraries, so does C. To even think you can compare Rust and C/C++ on that matter is not realistic.

I think that OP's point is that Haskell or Rust introduce enough of a different paradigm that it is worth thinking about them anew, rather than trying to map your old programming language knowledge to Rust or Haskell directly.

Then why even bother learning a new language if you have to deliver something fast and you know one already?