use regex escape sequences to shorten stuff up

actionpack/lib/action_view/helpers/number_helper.rb

@@ -64,9 +64,9 @@ def number_to_phone(number, options = {})
         country_code = options[:country_code]
 
         if area_code
-          number.gsub!(/([0-9]{1,3})([0-9]{3})([0-9]{4}$)/,"(\\1) \\2#{delimiter}\\3")
+          number.gsub!(/(\d{1,3})(\d{3})(\d{4}$)/,"(\\1) \\2#{delimiter}\\3")
         else
-          number.gsub!(/([0-9]{0,3})([0-9]{3})([0-9]{4})$/,"\\1#{delimiter}\\2#{delimiter}\\3")
+          number.gsub!(/(\d{0,3})(\d{3})(\d{4})$/,"\\1#{delimiter}\\2#{delimiter}\\3")
           number.slice!(0, 1) if number.starts_with?('-')
         end