Counterpoint: Rust.
Seems to be taking off (difficult to predict the long-term, of course), but Rust is excellent at functional paradigms and Brings many advancements of functional languages to the people.
Seems to be taking off (difficult to predict the long-term, of course), but Rust is excellent at functional paradigms and Brings many advancements of functional languages to the people.
Rust has constant functions, for one: https://doc.rust-lang.org/reference/const_eval.html
Rust functions (which don't take mutable references) are incapable of modifying anything you pass into them, and any sort of global state is heavily discouraged.
This is pretty good as far as "pure" goes, but of course, they can perform I/O. (Then again, without any side effects a program would do nothing at all behind heating up your CPU, so this seems like a fair trade-off.)
What makes Rust functional are the patterns you can use in the language, though. A lot ot of maps, a lot of filters, a lot of iterators and algebgaic data types and pattern matching.
Idk, looking pretty good to me, unless you think none of these count.
Considering everyone seems to hate C++ nowadays, and Rust looks like the only existing alternative. Hard to imagine the trend won't continue.