What sets apart creating an array with predefined elements and adding elements to a new array through iteration?

What sets apart declaring an array with elements from simply declaring it and iterating the elements into it in Javascript?

r = [req.body.email,
     req.body.password];

as opposed to

r=[];
r.push(req.body.email, req.body.password);

Answer №1

The most significant contrast lies in the readability of the code. Both options are practically identical in terms of functionality.

Depending on the specific JavaScript engine being used, one option may exhibit slightly better performance than the other, although this variance is typically minimal.

To accurately gauge performance, conducting tests on platforms like jsperf can provide valuable insights. Check out an example test here: http://jsperf.com/compare-assignment-vs-push/15

Running these assessments across multiple web browsers can yield varying outcomes. In my experience, direct assignment tends to offer slightly faster results.

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