parens validator

parens.js

let log = console.log.bind(console);
let test1 = "(asf(s)f)jkl(kl)l)l";
let test2 = "(hf)fh()(h(hf()h)gh)fffh";

log(validate(test1)); // --> false
log(validate(test2)); // --> true

function validate(str) {
  str = str.replace(/[^\(\)]/g, "");
  
  const lparens = (str.match(/\(/g) || []).length;
  const rparens = (str.match(/\)/g) || []).length;
  
  if(lparens !== rparens) {
  	return false;
  }
  
  let level = 0;
  for(let i = 0; i < str.length; i++) {
  	if(str[i] === "(") {
    	level++;
    } else if(str[i] === ")") {
    	level--;
    }
    
    if(level < 0) {
    	return false;
    }
  }
  return true;
}