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Can be accessed at:

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Join vs for

Benchmark created by polkovnikov.ph on March 24, 2016

Test runner

Ready to run.

Test Ops/sec

Join

Testing in
Test	Ops/sec
Join	`var a = new Array(100000).join("a") + "bcd";`	ready
for	`var a = "bcd"; for (var i = 0; i < 100000; ++i) { a = "a" + a; }`	ready
for binary	`var a = ""; for (var i = 100000, s = "a"; i != 0; i >>= 1) { if (i & 1) a += s; s += s; }`	ready

var a = new Array(100000).join("a") + "bcd";

ready

for

var a = "bcd";
for (var i = 0; i < 100000; ++i) {
    a = "a" + a;
}

ready

for binary

var a = "";
for (var i = 100000, s = "a"; i != 0; i >>= 1) {
    if (i & 1) a += s;
    s += s;
}

ready

Revisions

You can edit these tests or add more tests to this page by appending /edit to the URL.

Revision 1: published by polkovnikov.ph on March 24, 2016
Revision 5: published by Khoa Nguyen on March 24, 2016