Ix is more powerful than most other combinator libraries.

ix-example.js

function* fibonacci(){
  var fn1 = 1;
  var fn2 = 1;
  while (1){
    var current = fn2;
    fn2 = fn1;
    fn1 = fn1 + current;
    yield current;
  }
}

Ix.Enumerable.from(fibonacci())
  .take(10)
  .forEach(function (x, i) {
    console.log('Index: %s Value: %s', i, x);
  });
  
//=> Index: 0 Value: 1
//=> Index: 1 Value: 1
//=> Index: 2 Value: 2
//=> Index: 3 Value: 3
//=> Index: 4 Value: 5
//=> Index: 5 Value: 8
//=> Index: 6 Value: 13
//=> Index: 7 Value: 21
//=> Index: 8 Value: 34
//=> Index: 9 Value: 55