What high level languages support multithreading? [closed]
Erlang has built-in support for concurrent programming.
Strictly speaking, Erlang processe are greenlets. But the language and virtual machine are designed from the ground up to support concurrency. The language has specific control structures for asynchronous inter-process messaging.
In Python, greenlet is a third-party package that provides lightweight threads and channel-based messaging. But it does not bear the comparison with Erlang.
I suppose that the list of languages that are higher-level than Haskell is pretty short, and it has pretty good support for concurrency and parallelism.
With CPython, one has to remember about the GIL. To summarize: only one processor is used, even on multiprocessor machines. There are multiple ways around this, as the comment shows.