splice deletes from an array and also from its parent array - strange issue

Question

Hi I have this simple script in my code,

var c = [{a: 'apple'},{b: 'ball'},{c: 'ball'},{d: 'ball'}];
console.log(c); //prints 3 objects
var d = c; 
d.splice(0, 3);         
console.log(c); //prints 1 object        
console.log(d); //prints 1 object 

What is strange to me is both c and d after splice results same thing (after deleting 3 objects from c whereas I have deleted from d only not c). Using d.splice(0, 3) it should delete from 'd' why would it delete from 'c' too ??? any ideas ?? where am I missing something, pls guide me.

Answer 1

var d = c;

This is referencing the array, not duplicating it.

To duplicate it and make d a completely separate array, use .slice(0)

var d = c.slice(0)