Run results for: javascript replaceAt

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36

Browser: Chrome 131

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

Substr

24.8M/s

Array.split

45K/s

Array.from

37K/s

View exact numbers

Test name	Executions per second
✓ Substr	24,764,036 Ops/sec
Array.split	44,678 Ops/sec
Array.from	37,097 Ops/sec

HTML Preparation code:

<!--your preparation HTML code goes here-->

Script Preparation code:

// Set up
const replaceAt = (str, index, character) => str.substr(0, index) + character + str.substr(index+character.length);

const replaceAt2 = (str, index, character) => {
    const chars = Array.from(str);
    
    chars[index] = character;
    return chars.join('');
}

const replaceAt3 = (str, index, character) => {
    const chars = str.split('');
    
    chars[index] = character;
    return chars.join('');
}

// Set up test variables

const str = new Array(10000).fill('0123456789').join('0123456789');

Tests:

Substr
replaceAt(str, str.length / 2, "W");
Array.from
replaceAt2(str, str.length / 2, "W");
Array.split
replaceAt3(str, str.length / 2, "W");