es5.js
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'use strict';
var toStr = Object.prototype.toString;
var isPrimitive = require('./helpers/isPrimitive');
var isCallable = require('is-callable');
// http://ecma-international.org/ecma-262/5.1/#sec-8.12.8
var ES5internalSlots = {
'[[DefaultValue]]': function (O) {
var actualHint;
if (arguments.length > 1) {
actualHint = arguments[1];
} else {
actualHint = toStr.call(O) === '[object Date]' ? String : Number;
}
if (actualHint === String || actualHint === Number) {
var methods = actualHint === String ? ['toString', 'valueOf'] : ['valueOf', 'toString'];
var value, i;
for (i = 0; i < methods.length; ++i) {
if (isCallable(O[methods[i]])) {
value = O[methods[i]]();
if (isPrimitive(value)) {
return value;
}
}
}
throw new TypeError('No default value');
}
throw new TypeError('invalid [[DefaultValue]] hint supplied');
}
};
// http://ecma-international.org/ecma-262/5.1/#sec-9.1
module.exports = function ToPrimitive(input) {
if (isPrimitive(input)) {
return input;
}
if (arguments.length > 1) {
return ES5internalSlots['[[DefaultValue]]'](input, arguments[1]);
}
return ES5internalSlots['[[DefaultValue]]'](input);
};