Parse email addresses for "from" and "to" fields in Ruby

Yes, there's a gem for this; it's called mail.

require 'mail'addresses = []raw_addresses = Mail::AddressList.new("Abe Allen <a@a.com>, Bob Blue <b@b.com>, c@c.com")raw_addresses.addresses.each do |a|    address = {}  address[:address] = a.address  address[:name]    = a.display_name if a.display_name.present?  addresses << address      end

Assuming your data follows the examples you gave, this should work:

def extract_emails(string)  string.split(', ').map do |user_string|    if user_string.include? '<'      user_string =~ /^([^<]*)<([^>]*)>$/      {user: $1.strip, email: $2}    else      {user: nil, email: user_string}    end  endendextract_emails "a@a.com"                                          # => [{:user=>nil, :email=>"a@a.com"}]extract_emails "a@a.com, Bob Blue <b@b.com>"                      # => [{:user=>nil, :email=>"a@a.com"}, {:user=>"Bob Blue", :email=>"b@b.com"}]extract_emails "Abe Allen <a@a.com>, b@b.com"                     # => [{:user=>"Abe Allen", :email=>"a@a.com"}, {:user=>nil, :email=>"b@b.com"}]extract_emails "Abe Allen <a@a.com>, Bob Blue <b@b.com>"          # => [{:user=>"Abe Allen", :email=>"a@a.com"}, {:user=>"Bob Blue", :email=>"b@b.com"}]extract_emails "Abe Allen <a@a.com>, Bob Blue <b@b.com>, c@c.com" # => [{:user=>"Abe Allen", :email=>"a@a.com"}, {:user=>"Bob Blue", :email=>"b@b.com"}, {:user=>nil, :email=>"c@c.com"}]

I don't know of a library, but if you are trying to get a list of the emails you could do the following yourself. (Long winded on purpose)

@a = "Abe Allen <a@a.com>, Bob Blue <b@b.com>, c@c.com"b = @a.split(',') #=> ["Abe Allen <a@a.com>", " Bob Blue <b@b.com>", " c@c.com"] c = b.collect{|x| x[/<(.*?)>|^([^<>]*)$/]} #=> ["<a@a.com>", "<b@b.com>", " c@c.com"] d = c.gsub(/[<>]/,'') #=> ["a@a.com", "b@b.com", " c@c.com"] 

If you want to match their names and email addresses, you will need something else.

Also, this won't work if there are '<' or '>' in the email address, but that's pretty uncommon.