1 files changed, 25 insertions, 0 deletions
diff --git a/lib/nickserver/email_address.rb b/lib/nickserver/email_address.rb
new file mode 100644
index 0000000..26053a2
--- /dev/null
+++ b/lib/nickserver/email_address.rb
@@ -0,0 +1,25 @@
+#
+# This rather crazy regexp is from here: http://code.iamcal.com/php/rfc822/
+# Licensed GPLv3
+#
+# It is too liberal, allowing "!@x" as a valid address, for example, but it does
+# follow the specification rather closely.
+#
+
+module Nickserver
+  EmailAddress = begin
+    qtext = '[^\\x0d\\x22\\x5c\\x80-\\xff]'
+    dtext = '[^\\x0d\\x5b-\\x5d\\x80-\\xff]'
+    atom = '[^\\x00-\\x20\\x22\\x28\\x29\\x2c\\x2e\\x3a-\\x3c\\x3e\\x40\\x5b-\\x5d\\x7f-\\xff]+'
+    quoted_pair = '\\x5c[\\x00-\\x7f]'
+    domain_literal = "\\x5b(?:#{dtext}|#{quoted_pair})*\\x5d"
+    quoted_string = "\\x22(?:#{qtext}|#{quoted_pair})*\\x22"
+    domain_ref = atom
+    sub_domain = "(?:#{domain_ref}|#{domain_literal})"
+    word = "(?:#{atom}|#{quoted_string})"
+    domain = "#{sub_domain}(?:\\x2e#{sub_domain})*"
+    local_part = "#{word}(?:\\x2e#{word})*"
+    addr_spec = "#{local_part}\\x40#{domain}"
+    /\A#{addr_spec}\z/n
+  end
+end