Check if String is a valid email address

email_validation.rb

class String
  VALID_EMAIL_REGEX = /\A[\w+\-.]+@[a-z\d\-.]+\.[a-z]+\z/i
  
  def is_valid_email?
    if self.match(VALID_EMAIL_REGEX)
      return true
    else
      return false
    end  
  end
end