Coming Soon

Sneak peek::

import Rx = "rx";

def even(x: Number): Boolean =
    rem(x, 2) = 0;

def sqrt(x: Number)(require !isNaN(x) -> x >= 0): Number =
    Math.sqrt(x);

def main(input) =
    input
    |> filter(even)
    |> map(sqrt)
    |> forEach(x => console.log(x));

main(range() |> take(10));

let field = document.getElementById('number-field');
main(Rx.Observable.fromEvent(field, 'input')
     |> map(e => e.target.value)
     |> map(x => parseInt(x)));