The primitive types (number, string, etc.) are passed by value, but objects are unknown, because they can be both passed-by-value (in case we consider that a variable holding an object is in fact a reference to the object) and passed-by-reference (...

This question already has answers here:...

I know that in JS, objects are passed by reference, for example:  function test(obj) {     obj.name = 'new name'; }  var my_obj = { name: 'foo' }; test(my_obj); alert(my_obj.name); // new name   But why doesn't the below work:...

This question already has answers here:...

All my unit tests have some common code I can run and abstract into a function. However I want to be able to re-use the Core value in every test  function makeSuite(name, module, callback) {     suite(name, function () {         var Core = {};...

I just found out the hard way objects are passed by reference in Javascript, for example:  for(var layer = 0; layer < hudLayers['layers'].length; layer++){      // Store the to-be-calculated values in this object     var tempValues = hudLa...

In my React-Redux app, I am changing the redux state and it looks something like this  state {     key1: oldVal1     key2: oldArray1 //The value here is an array     .     .     . }   Now when I update the state next time...  state {     key1: newVal...

I was trying to understand passing of variables and objects in JavaScript, and came across this page.  It is explained that JavaScript objects are passed by value, but the value itself is a reference. Though I understood what was happening in the exa...

Given an object obj, I can modify its properties by using something like obj.a.b.c = "new value". However, I want to be able to do this programmatically, with the property's location in the form of an array. How can I make a function that...

We all know JS has objects and a group of primitives.  Let's examine the following assignments.  a = 'foo'; b = a; c = 'foo' a === b; //true a = b = c = undefined;   The way I visualize the variable assignment process in JS for ye...