Choices/assets/scripts/src/lib/polyfills.js

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// Production steps of ECMA-262, Edition 6, 22.1.2.1
// Reference: https://people.mozilla.org/~jorendorff/es6-draft.html#sec-array.from
if (!Array.from) {
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Array.from = (function() {
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var toStr = Object.prototype.toString;
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var isCallable = function(fn) {
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return typeof fn === 'function' || toStr.call(fn) === '[object Function]';
};
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var toInteger = function(value) {
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var number = Number(value);
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if (isNaN(number)) {
return 0;
}
if (number === 0 || !isFinite(number)) {
return number;
}
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return (number > 0 ? 1 : -1) * Math.floor(Math.abs(number));
};
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var maxSafeInteger = Math.pow(2, 53) - 1;
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var toLength = function(value) {
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var len = toInteger(value);
return Math.min(Math.max(len, 0), maxSafeInteger);
};
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// The length property of the from method is 1.
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return function from(arrayLike /*, mapFn, thisArg */ ) {
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// 1. Let C be the this value.
var C = this;
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// 2. Let items be ToObject(arrayLike).
var items = Object(arrayLike);
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// 3. ReturnIfAbrupt(items).
if (arrayLike == null) {
throw new TypeError("Array.from requires an array-like object - not null or undefined");
}
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// 4. If mapfn is undefined, then let mapping be false.
var mapFn = arguments.length > 1 ? arguments[1] : void undefined;
var T;
if (typeof mapFn !== 'undefined') {
// 5. else
// 5. a If IsCallable(mapfn) is false, throw a TypeError exception.
if (!isCallable(mapFn)) {
throw new TypeError('Array.from: when provided, the second argument must be a function');
}
// 5. b. If thisArg was supplied, let T be thisArg; else let T be undefined.
if (arguments.length > 2) {
T = arguments[2];
}
}
// 10. Let lenValue be Get(items, "length").
// 11. Let len be ToLength(lenValue).
var len = toLength(items.length);
// 13. If IsConstructor(C) is true, then
// 13. a. Let A be the result of calling the [[Construct]] internal method of C with an argument list containing the single item len.
// 14. a. Else, Let A be ArrayCreate(len).
var A = isCallable(C) ? Object(new C(len)) : new Array(len);
// 16. Let k be 0.
var k = 0;
// 17. Repeat, while k < len… (also steps a - h)
var kValue;
while (k < len) {
kValue = items[k];
if (mapFn) {
A[k] = typeof T === 'undefined' ? mapFn(kValue, k) : mapFn.call(T, kValue, k);
} else {
A[k] = kValue;
}
k += 1;
}
// 18. Let putStatus be Put(A, "length", len, true).
A.length = len;
// 20. Return A.
return A;
};
}());
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}
// Reference: https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Array/find
if (!Array.prototype.find) {
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Array.prototype.find = function(predicate) {
'use strict';
if (this == null) {
throw new TypeError('Array.prototype.find called on null or undefined');
}
if (typeof predicate !== 'function') {
throw new TypeError('predicate must be a function');
}
var list = Object(this);
var length = list.length >>> 0;
var thisArg = arguments[1];
var value;
for (var i = 0; i < length; i++) {
value = list[i];
if (predicate.call(thisArg, value, i, list)) {
return value;
}
}
return undefined;
};
}
(function() {
"use strict";
var lastTime = 0,
vendors = ['ms', 'moz', 'webkit', 'o'],
x;
for (x = 0; x < vendors.length && !window.requestAnimationFrame; ++x) {
window.requestAnimationFrame = window[vendors[x] + 'RequestAnimationFrame'];
window.cancelAnimationFrame = window[vendors[x] + 'CancelAnimationFrame'] ||
window[vendors[x] + 'CancelRequestAnimationFrame'];
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}
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if (!window.requestAnimationFrame) {
window.requestAnimationFrame = function(callback, element) {
var currTime = new Date().getTime(),
timeToCall = Math.max(0, 16 - (currTime - lastTime)),
id = window.setTimeout(function() {
callback(currTime + timeToCall);
}, timeToCall);
lastTime = currTime + timeToCall;
return id;
};
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}
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if (!window.cancelAnimationFrame) {
window.cancelAnimationFrame = function(id) {
window.clearTimeout(id);
};
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}
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}());