Would an array that is always acessed better be global or local?

Asked Jun 10 '20 at 11:40

Active Jun 10 '20 at 11:47

Viewed 26 times

Imagine this javascript code is inside an already busy loop:

if (a==0)
{
     d=6;
}else if (a==1)
{
     d=31;
}else if (a==2)
{
     d=null;
}

I thought of replacing it with:

var array=[6,31,null];
d=array[a];

Which would be faster? In case it is the array approach, is it faster to have this array as a global var? I am thinking "Yes, because if you make it local, the program becomes a bit slower because it has to declare the array every time". Thank you in advance.

edited Jun 10 '20 at 11:47

asked Jun 10 '20 at 11:40

Jorge Al Najjar

1

Should the third comparison be `a==2`? Other wise the array would need to be something like `[6, 31, "", null]` – Run_Script Jun 10 '20 at 11:42
yeah, my bad :) – Jorge Al Najjar Jun 10 '20 at 11:47
1

Personally I think I would go with the nice and short approach of declaring the array as global and then using `d=array[a]` like you suggested, but I'll guess you'll see what turns out to be best when you do the performance test that has been recommended to you. – Run_Script Jun 10 '20 at 11:49
Another idea would be to use a `Map`. – Heretic Monkey Jun 10 '20 at 11:51

Would an array that is always acessed better be global or local?

0 Answers0