kerneloops

Another one:

  const cast: <A, B> (a: A) => B = function <B> (): B {
    return arguments[0]
  }
  const n: string = cast(1)

A survey of some other languages:

C printf: MT-Safe locale.

C++ std::cout: safe, unless you call sync_with_stdio(false).

JVM System.out.println: safe in common JVMs.

C# Console.WriteLine: safe.

Go fmt.Printf: safe.

Rust println!: safe.

Ruby puts: safe.

So it seems that Python is the outlier here.

> Using these accessors, the VMs become able to do anything that JS can do.

In fact the source language is likely to be JS itself; a JS-to-some-sort-of-vm-bytecode-to-JS compiler is made. I know that Tencent has a similar VM; an interesting aspect of that VM is that the instruction set is dependent on the code being compiled (and the opcodes are dynamically generated and shuffled when compiling), so unused instructions are not generated.