function extend(object,data){for(var key in data){object[key]=data[key]}return object};
var a = [{c:0,d:0},{c:1,d:1},{c:2,d:2}]
var b = []
b.push( extend({},a[0]) ); //b.push(a[0])
b[0].c = 1;
console.log(b) //[{c: 1, d: 0}]
console.log(a) //[{c: 0, d: 0},{c: 1, d: 1},{c: 2, d: 2}]
