From: Eric Wong <normalperson@...>
Date: 2011-12-16T08:30:15+09:00
Subject: Re: perf optimization using profile results

Chuck Remes <cremes.devlist@mac.com> wrote:
> 6. In hot code when looking up a value in an array, it's a tad faster
> to use #at instead of #[]. The reason is that #[] can take different
> arguments other than a simple index (like a Range). Those extra
> argument checks can add up.

> These are all micro-optimizations and may not even be valid on your
> runtime of choice.

Exactly.

Array#at shouldn't be faster than Array#[] on MRI 1.9+ with a single arg
(ref: insns.def).