locutus/esm/c/stdlib/atoi.js

Locutus other languages' standard libraries to JavaScript for fun and educational purposes

export function atoi(str) {
    //      discuss at: https://locutus.io/c/stdlib/atoi/
    // parity verified: C 23
    //     original by: Kevin van Zonneveld (https://kvz.io)
    //          note 1: Converts a string to an integer.
    //          note 1: Parses until first non-numeric character.
    //       example 1: atoi('42')
    //       returns 1: 42
    //       example 2: atoi('  -123abc')
    //       returns 2: -123
    //       example 3: atoi('abc')
    //       returns 3: 0
    str = (str + '').replace(/^\s+/, '');
    const result = parseInt(str, 10);
    return isNaN(result) ? 0 : result;
}