JS String extension with codes and chars

string_extensions.js

/**
 * Gives char codes of the string
 * @author TheRolf
 */
String.prototype.codes = function() {
    return this.split('').map(c => {
        let code = c.charCodeAt(0); 
        return code;
    }).flat()
}

/**
 * Gives chars of characters of the string, big-endian 
 * @author TheRolf
 */
String.prototype.chars = function() {
    return this.split('').map(c => {
        let code = c.charCodeAt(0);

        let arr = [];
        while(code > 0) {
            let b = code & 255;
            arr = [b, ...arr];
            code = code >> 8;
        }
        
        return arr;
    }).flat()
}