Run results for: lodash.head() vs [0]

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.163 Whale/2.7.100.20 Safari/537.36

Browser: Chrome 80

Operating system: Mac OS X 10.15.5

Device Platform: Desktop

Date tested: 4 years ago

Test name	Executions per second
Not empty lodash.head()	4145448.8 Ops/sec
Not empty [0]	14495933.0 Ops/sec
Empty lodash.head()	4447185.0 Ops/sec
Empty [0]	14513339.0 Ops/sec
[0] with check	4507056.0 Ops/sec
[0] with null check	3455116.2 Ops/sec

HTML Preparation code:


<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js'></script>

Script Preparation code:

var a = [1,2,3];
var e = [];

Tests:

Not empty lodash.head()
_.head(a)
Not empty [0]
a[0]
Empty lodash.head()
_.head(e)
Empty [0]
e[0]
[0] with check
e.length ? e[0] : undefined
[0] with null check
e && e.length ? e[0] : undefined

Run results for: lodash.head() vs [0]

Is head() needed only to check length !== 0 ? P.s. Empty testcase for [0] is useless because it won't crash on trying to get nonexistent element

Not empty lodash.head()

Not empty [0]

Empty lodash.head()

Empty [0]

[0] with check

[0] with null check