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Comment by winterbe | Hacker News Reader

For JavaScript using Stream.js https://github.com/winterbe/streamjs

  var total = Stream
        .iterate(0, function (n) {
            return n + 1;
        })
        .map(function (x) {
            return x * x;
        })
        .limit(10)
        .sum();

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Lazy.js, with ES6 arrow functions:

  var Lazy = require('lazy.js');

  var total = Lazy
    .generate(i => i + 1)
    .map(i => i * i)
    .take(10)
    .sum();

C#, with LINQ:

  IEnumerable<int> NaturalNumbers()
  {
    var i = 1;
	
    while (true)
      yield return i++;
  }

  var total = NaturalNumbers().Select(n => n * n).Take(10).Sum();

As, of course, int has a maximum, it would be more sensible to use:

  Enumerable.Range(1, int.MaxValue).Select(n => n * n).Take(10).Sum();

And if you already know that you want 10, as in the above, you'd likely do:

  Enumerable.Range(1, 10).Select(n => n * n).Sum();

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