Comment by mamcx
13 hours ago
Well, what means to support, truly, TVars?
Is easy, or hard?
Demand a new paradigm at large, or is only a inconvenience in the few places is used?
Because if the answer is "turns the language into Haskell" then is a big NOPE!
Well, Haskell is a big language with lots of different aspects.
To nicely support TVars, it's good if your language can differentiate between pure code and code with side-effects. Haskell's type system is one way to get there; but eg something like Rust could probably also be coerced to do something appropriate.
Apart from that, you probably don't even need static typing to make it work well enough (though it probably helps). You definitely don't need laziness or Haskell's love of making up new operators or significant whitespace.
Here is a C++ STM based on the Haskell STM API:
https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n44...