Bend/examples/callcc.hvm

Seq a b = a

// Create a program capable of using `callcc`
CC.lang = λprogram
  let callcc  = λcallback (λ$garbage($hole) (callback λ$hole(0)));
  let result  = (program callcc);
  let garbage = $garbage; // Discard `$garbage`, which is the value returned by `callback`
  (Seq result garbage)

Main = (CC.lang λcallcc 
  // This code calls `callcc`, then calls `k` to fill the hole with `42`. This means that the call to callcc returns `42`, and the program returns `52`
  (+ 10 (callcc λk(+ (k 42) 1729)))
)