1 files changed, 5 insertions, 2 deletions
diff --git a/lib/un.rb b/lib/un.rb
index 24c6024c71..907b80c0ab 100644
--- a/lib/un.rb
+++ b/lib/un.rb
@@ -43,8 +43,11 @@ def setup(options = "", *long_options)
       end
     end
     long_options.each do |s|
-      opt_name = s[/\A(?:--)?([^\s=]+)/, 1].intern
-      o.on(s.gsub(/([a-z])([A-Z])/){$1+"-"+$2.downcase}.sub(/\A(?!--)/, '--')) do |val|
+      opt_name, arg_name = s.split(/(?=[\s=])/, 2)
+      opt_name.sub!(/\A--/, '')
+      s = "--#{opt_name.gsub(/([A-Za-z]+)([A-Z])/, '\1-\2').downcase}#{arg_name}"
+      opt_name = opt_name.intern
+      o.on(s) do |val|
         opt_hash[opt_name] = val
       end
     end