koka-lang

2021-12-31 · 1 min read

functions literally all the way down (mod some primitives)
algebraic effects nicely integrated into the language at all levels
first-class effect type, composes nicely, allows user-defined control flow, almost all control syntax (e.g. while, for, ..) is actually just functions
- fun for ( start : int, end : int, action : (int) -> e ()) : e ()
- fun while( pred : () -> <div|e> bool, action : () -> <div|e> () ) : <div|e> ()
  - note: <div|e> means polymorphic effect e union effect div (divergent, possibly non-terminating)
universal dot call syntax! myint.double == double(myint)
effects effectively specify an "interface" of handlers, which can be overridden
very curious how extensive non-linear control flow affects performance : )