regex pattern for email domain code example

Example 1: email regex

//Author: Mohammad Arman Khan
//Regular Expresssion for e-mail validation
var email_validator_regex = /^[a-zA-Z0-9.!#$%&'*+/=?^_`{|}~-]+@[a-zA-Z0-9-]+(?:\.[a-zA-Z0-9-]+)*$/;

Example 2: email regex

#found on stackoverflow
([a-zA-Z0-9_.+-]+@[a-zA-Z0-9-]+\.[a-zA-Z0-9-.]+)
#to put all mails in a list from a string that refers to an html text code 
emails = re.findall("([a-zA-Z0-9_.+-]+@[a-zA-Z0-9-]+\.[a-zA-Z0-9-.]+)", html_text)