transpiler.js

var STRIP_COMMENTS = /((\/\/.*$)|(\/\*[\s\S]*?\*\/))/mg;
var ARGUMENT_NAMES = /([^\s,]+)/g;
function getParamNames(func) {
    var fnStr = func.toString().replace(STRIP_COMMENTS, '');
    var result = fnStr.slice(fnStr.indexOf('(')+1, fnStr.indexOf(')')).match(ARGUMENT_NAMES);
    if(result === null)
	result = [];
    return result;
}

function a(b, c) {
}

let params = getParamNames(a);

console.log(params);