How to get the javascript function parameter names/values dynamically ?

// JavaScript program to get the function
// name/values dynamically
function getParams(func) {

    // String representation of the function code
    let str = func.toString();

    // Remove comments of the form /* ... */
    // Removing comments of the form //
    // Remove body of the function { ... }
    // removing '=>' if func is arrow function 
    str = str.replace(/\/\*[\s\S]*?\*\//g, '')
        .replace(/\/\/(.)*/g, '')
        .replace(/{[\s\S]*}/, '')
        .replace(/=>/g, '')
        .trim();

    // Start parameter names after first '('
    let start = str.indexOf("(") + 1;

    // End parameter names is just before last ')'
    let end = str.length - 1;

    let result = str.substring(start, end).split(", ");

    let params = [];

    result.forEach(element => {

        // Removing any default value
        element = element.replace(/=[\s\S]*/g, '').trim();

        if (element.length > 0)
            params.push(element);
    });

    return params;
}

// Test sample functions
let fun1 = function (a) { };

function fun2(a = 5 * 6 / 3, 
b) { };

let fun3 = (a, /*
        */
    b, //comment
    c) => /** */ { };

console.log(`List of parameters of ${fun1.name}:`, 
    getParams(fun1));
console.log(`List of parameters of ${fun2.name}:`, 
    getParams(fun2));
console.log(`List of parameters of ${fun3.name}:`, 
    getParams(fun3));