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/**
* Simplified version of es5-sham#Object-create that also works around a bug
* in the actual es5-sham: https://github.com/es-shims/es5-shim/issues/252
*
* Does not:
* - Support empty inheritance via `Object.create(null)`.
* - Support getter and setter accessors via `Object.create( .., properties )`.
* - Support custom property descriptor (e.g. writable, configurtable, enumerable).
* - Leave behind an enumerable "__proto__" all over the place.
*
* @author Timo Tijhof, 2014
*/
// ES5 15.2.3.5
// http://es5.github.com/#x15.2.3.5
if ( !Object.create ) {
( function () {
var hasOwn = Object.hasOwnProperty,
// https://developer.mozilla.org/en-US/docs/ECMAScript_DontEnum_attribute#JScript_DontEnum_Bug
// http://whattheheadsaid.com/2010/10/a-safer-object-keys-compatibility-implementation
isEnumBug = !{ valueOf: 0 }.propertyIsEnumerable( 'valueOf' );
// Reusable constructor function for Object.create
function Empty() {}
function defineProperty( object, key, property ) {
if ( hasOwn.call( property, 'value' ) ) {
object[ key ] = property.value;
} else {
object[ key ] = property;
}
}
Object.create = function create( prototype, properties ) {
var object, key;
if ( prototype !== Object( prototype ) ) {
throw new TypeError( 'Called on non-object' );
}
Empty.prototype = prototype;
object = new Empty();
if ( properties !== undefined ) {
if ( !isEnumBug ) {
for ( key in properties ) {
if ( hasOwn.call( properties, key ) ) {
defineProperty( object, key, properties[ key ] );
}
}
} else {
Object.keys( properties ).forEach( function ( key ) {
defineProperty( object, key, properties[ key ] );
} );
}
}
return object;
};
}() );
}
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