Why is this array being passed by reference and not by value, and how can I change this? [duplicate]

Question

I was working on a bug in some code that I wrote, and the culprit turned out to be this snippet (simplified for the sake of the question):

var a = [1, 2, 3, 5, 4]; // later... function f(arr) { var sorted = arr.sort(); // other stuff } // later... console.log(a); // logs [1, 2, 3, 4, 5]!

My question is, why does a stay sorted after the function is done? Surely in JS all variables are passed by value as opposed to reference?

I believe this answers your question stackoverflow.com/questions/2835070/… — Dai
– Dai, Commented Nov 19, 2014 at 9:09

Community · Accepted Answer · 2017-05-23 12:27:26Z

0

Look at this for a full description

Is JavaScript a pass-by-reference or pass-by-value language?

edited May 23, 2017 at 12:27

CommunityBot

11 silver badge

answered Nov 19, 2014 at 9:16

Luca Rasconi

1,1051 gold badge11 silver badges34 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

georg Over a year ago

Sorry, but this should be a comment, not an answer.

Luca Rasconi Over a year ago

You are right but I can't add comments.

murli2308 · Accepted Answer · 2014-11-19 09:19:55Z

-1

Array is an Object. In javascript all Objects are passed by reference.

answered Nov 19, 2014 at 9:19

murli2308

3,0224 gold badges31 silver badges47 bronze badges

3 Comments

georg Over a year ago

Sorry, but this answer is wrong. Javascript doesn't have "pass by reference" (like in C++ or PHP).

murli2308 Over a year ago

Objects are passed by reference only in javascript and I am sure about it. I made a simple fiddle for it. jsfiddle.net/murli2308/npag0fj4

georg Over a year ago

This topic has been discussed ad nauseum, please read the answers in the linked thread. In short, js passes everything by value, but this very value is always a reference (=pointer).

Collectives™ on Stack Overflow

Why is this array being passed by reference and not by value, and how can I change this? [duplicate]

2 Answers 2

2 Comments

3 Comments

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

3 Comments

Linked

Related