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Array indexOf prototyping for IE8
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if (!Array.prototype.indexOf) { | |
Array.prototype.indexOf = function (searchElement /*, fromIndex */ ) { | |
"use strict"; | |
if (this == null) { | |
throw new TypeError(); | |
} | |
var t = Object(this); | |
var len = t.length >>> 0; | |
if (len === 0) { | |
return -1; | |
} | |
var n = 0; | |
if (arguments.length > 1) { | |
n = Number(arguments[1]); | |
if (n != n) { // para verificar si es NaN | |
n = 0; | |
} else if (n != 0 && n != Infinity && n != -Infinity) { | |
n = (n > 0 || -1) * Math.floor(Math.abs(n)); | |
} | |
} | |
if (n >= len) { | |
return -1; | |
} | |
var k = n >= 0 ? n : Math.max(len - Math.abs(n), 0); | |
for (; k < len; k++) { | |
if (k in t && t[k] === searchElement) { | |
return k; | |
} | |
} | |
return -1; | |
} | |
} |
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