Run results for: Unnecessary non-capturing groups

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/59.0.3071.115 Safari/537.36

Browser: Chrome 59

Operating system: Linux

Device Platform: Other

Date tested: 7 years ago

Test name	Executions per second
unneededNonCaptureRE	2054305.4 Ops/sec
noNonCaptureRE	2049817.9 Ops/sec
anotherUnneededNonCapture	2643922.0 Ops/sec
anotherNoNonCapture	2122956.5 Ops/sec

Script Preparation code:

var loremString = "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum."
var unneededNonCaptureRE = /(?:z)+/
var noNonCaptureRE = /z+/
var anotherUnneededNonCapture = /lab(?:o)rum/
var anotherNoNonCapture = /laborum/

Tests:

unneededNonCaptureRE
unneededNonCaptureRE.lastIndex = 0 unneededNonCaptureRE.exec(loremString)
noNonCaptureRE
noNonCaptureRE.lastIndex = 0 noNonCaptureRE.exec(loremString)
anotherUnneededNonCapture
anotherUnneededNonCapture.lastIndex = 0 anotherUnneededNonCapture.exec(loremString)
anotherNoNonCapture
anotherNoNonCapture.lastIndex = 0 anotherNoNonCapture.exec(loremString)

Run results for: Unnecessary non-capturing groups

https://stackoverflow.com/questions/45291700/javascript-regex-non-capture-faster-than-no-parenthesis-at-all

unneededNonCaptureRE

noNonCaptureRE

anotherUnneededNonCapture

anotherNoNonCapture