1
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'use strict';
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2
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3
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var toStr = Object.prototype.toString;
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4
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5
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var isPrimitive = require('./helpers/isPrimitive');
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6
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7
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var isCallable = require('is-callable');
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8
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9
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// http://ecma-international.org/ecma-262/5.1/#sec-8.12.8
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10
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var ES5internalSlots = {
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11
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'[[DefaultValue]]': function (O) {
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12
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var actualHint;
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13
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if (arguments.length > 1) {
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14
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actualHint = arguments[1];
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15
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} else {
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16
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actualHint = toStr.call(O) === '[object Date]' ? String : Number;
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17
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}
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18
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19
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if (actualHint === String || actualHint === Number) {
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20
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var methods = actualHint === String ? ['toString', 'valueOf'] : ['valueOf', 'toString'];
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21
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var value, i;
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22
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for (i = 0; i < methods.length; ++i) {
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23
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if (isCallable(O[methods[i]])) {
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24
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value = O[methods[i]]();
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25
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if (isPrimitive(value)) {
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26
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return value;
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27
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}
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28
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}
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29
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}
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30
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throw new TypeError('No default value');
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31
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}
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32
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throw new TypeError('invalid [[DefaultValue]] hint supplied');
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33
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}
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34
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};
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35
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36
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// http://ecma-international.org/ecma-262/5.1/#sec-9.1
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37
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module.exports = function ToPrimitive(input) {
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38
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if (isPrimitive(input)) {
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39
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return input;
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40
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}
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41
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if (arguments.length > 1) {
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42
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return ES5internalSlots['[[DefaultValue]]'](input, arguments[1]);
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43
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}
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44
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return ES5internalSlots['[[DefaultValue]]'](input);
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45
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};
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