Run results for: Regex vs split/join - actual replace

Now regex flies and split crawls. BTW that regex match split plus join is what jQuery's removeClass() does - just much worse. Had to double check just in case that there's some hidden trick involved.

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.132 Safari/537.36

Browser: Chrome 80

Operating system: Mac OS X 10.14.6

Device Platform: Desktop

Date tested: 4 years ago

Test name	Executions per second
Regex	1156989.0 Ops/sec
Regex match as Split - jQuery style :-)	383572.7 Ops/sec
Split and Join	344811.8 Ops/sec

Script Preparation code:

var sep = "[\x20\t\r\n\f]";
var not_sep = "[^\x20\t\r\n\f]";

var str = 'Abcd efghij klmnopqrstuv wxy Abcd efghij klmnopqrstuv wxy Abcd efghij klmnopqrstuv wxyAbcd efghij klmnopqrstuv wxy Abcd efghij klmnopqrstuv wxy Abcd efghij klmnopqrstuv wxy';

Tests:

Regex
var name = "skin-oasis|background-dynamic"; let re = new RegExp(name + "(?:" + sep + "+|$)"); var res = str.replace(re, "");
Regex match as Split - jQuery style :-)
let re = new RegExp(not_sep + "+", 'g'); let arr = str.match(re); for (i = 0; i < arr.length; ++i) { if ( arr[i] == "skin-oasis" ) arr[i] = null; } arr.join(" ");
Split and Join
let re = new RegExp(name + "(?:" + sep + "|$)"); let arr = str.split(re); for (i = 0; i < arr.length; ++i) { if ( arr[i] == "skin-oasis" ) arr[i] = null; } arr.join(" ");

Run results for: Regex vs split/join - actual replace

Now regex flies and split crawls. BTW that regex match split plus join is what jQuery's removeClass() does - just much worse. Had to double check just in case that there's some hidden trick involved.

Regex

Regex match as Split - jQuery style :-)

Split and Join