getting a string length that contains unicode character exceeding 0xffff

Question

I’m using this character, double sharp \'

Answer 1

String.prototype.codes = function() { return [...this].length };
String.prototype.chars = function() {
    let GraphemeSplitter = require('grapheme-splitter');
    return (new GraphemeSplitter()).countGraphemes(this);
}

console.log("F