Regex for valid email

valid_email.md

regex valid update

const validEmail(str) => !/(\.{2}|-{2}|_{2})/.test(val) && /^[a-z0-9][a-z0-9-_\.]+@[a-z0-9]+([a-z0-9-])?[a-z0-9]\.[a-z]{2,10}(?:\.[a-z]{2,10})?$/.test(val);

validEmail('admin@gmail.com'); //true
validEmail('.admin@gmail.com'); //false
validEmail('admin--admin@gmail.com'); //false
validEmail('admin@-myapp-.com'); //false
validEmail('admin@my-large-domain.news'); //valid
validEmail('admin@comercio.com.pe'); //valid
validEmail('ud@se.cz'); //valid

more use cases: https://regex101.com/r/2ZKtyk/2/tests