Proper way of multiple variable assignment in Javascript
This question already has an answer here:
It is not okay, since those 2 code examples are not identical. The first one equals to:
var b1;
b4 = 100;
b3 = b4;
b2 = b3;
b1 = b2;
So you only define b1 in the local scope, the b2..b4 are declared globally. Which means this MUST BE completely avoided.
I also highly doubt console.log(b1); outputs 100 as per your example.
(function(){
var b1 = b2 = b3 = b4 = 100;
})();
console.log(b1); //100 <-- this is not true
console.log(b2); //100
console.log(b3); //100
console.log(b4); //100
From the other hand - for already declared variables - initialization or assignment using
// we assume a, b and c have been declared already
a = b = c = 100;
is a subject of your project/team conventions. From technical perspective it's fine to use it.
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