Analysis of continuous assignment problem examples in JavaScript

This article describes the continuous assignment problem in JavaScript. Share it for your reference, as follows:

Continuous assignment in JavaScript:

<script>
var a = {n: 1}
var b = a;
 = a = {n: 2}
();//undefined
()//Object {n: 2}
</script>

The priority of the assignment operator "=" in Javascript is the lowest except "," and is combined from right to left.

The order of operations in Javascript is from left to right.

= a = {n: 2}Can be seen as =(a = {n: 2}), first perform calculation, add x attribute to a, the result isnull, in the calculation expression(a = {n: 2}), and finally perform the assignment operation.

Modify the program:

<script>
var a = {n: 1}
var b = a;
a =  = {n: 2}
();//undefined
()//Object {n: 2}
</script>

<script>
var a = {x:{xx:1},y:2,z:3};
var b = ; //{xx:1}
var c = a;
 =  =  = a = {x:10,y:20};
(a);
(b);
(c);
</script>

Running results:

a : {x: 10, y: 20}
b : {xx : {x: 10, y: 20}}
c :?{x:{xx:{x:10,y:20}},y:{x:10,y:20},z:3,w:{x:10,y:20}}

<script>
();//10
();//10
();//10
</script>

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For more information about JavaScript, you can also view the topic of this site: "JavaScript object-oriented tutorial》、《Summary of JavaScript Errors and Debugging Skills》、《Summary of JavaScript data structure and algorithm techniques》、《JavaScript traversal algorithm and skills summary"and"Summary of JavaScript mathematical operations usage》

I hope this article will be helpful to everyone's JavaScript programming.