JavaScript Teaser: Fabulous Fibonacci

Written by Yuri Takhteyev

Fill in the missing line of the following code that implements a function returning the next Fibonacci number every time it's called.

  var nextFibonacciNumber = (function() {
    var s = [0, 1];
    return function () {
      // Fill in the missing line here.
      return s.shift();

You should only need to add a single statement, consisting of less than 25 characters.

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