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MACSkeptic/good-morning.js

Created July 29, 2013 10:09
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callback is invoked only for indexes of the array which have assigned values (from: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/map)
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good-morning.js
[1, 2].map(function (x) { return x; }) // -> [1, 2]
[1,, 2].map(function (x) { return x; }) // -> [1, undefined × 1, 2]
[1, 2].map(function () { return 'constant'; }) // -> ["constant", "constant"]
[1,, 2].map(function () { return 'constant'; }) // -> ["constant", undefined × 1, "constant"]
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