convert_without_area_code

# File activesupport/lib/active_support/number_helper/number_to_phone_converter.rb, line 31
        def convert_without_area_code(number)
          default_pattern = /(\d{0,3})(\d{3})(\d{4})$/
          number.gsub!(regexp_pattern(default_pattern),
                       "\\1#{delimiter}\\2#{delimiter}\\3")
          number.slice!(0, 1) if start_with_delimiter?(number)
          number
        end