Fastest way to duplicate an array in JavaScript - slice vs. 'for' loop

Question

Can anyone help me to get which is the fastest way to duplicate an array using in JavaScript?

Answer 1

Basically, the fastest one will depends on the browser like for Blink browser slice() is fastest, whereas for other browsers while loop is fastest. Also, you can use the below code to test in the browser console:

While Loop:

n = 1000*1000;

start = + new Date();

a = Array(n); 

b = Array(n); 

i = a.length;

while(i--) b[i] = a[i];

console.log(new Date() - start);

Slice :

n = 1000*1000;

start = + new Date();

a = Array(n); 

b = a.slice();

console.log(new Date() - start);

I hope this will help.

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