use_proxy?

# File lib/uri/generic.rb, line 1545
    def self.use_proxy?(hostname, addr, port, no_proxy) # :nodoc:
      hostname = hostname.downcase
      dothostname = ".#{hostname}"
      no_proxy.scan(/([^:,\s]+)(?::(\d+))?/) {|p_host, p_port|
        if !p_port || port == p_port.to_i
          if p_host.start_with?('.')
            return false if hostname.end_with?(p_host.downcase)
          else
            return false if dothostname.end_with?(".#{p_host.downcase}")
          end
          if addr
            begin
              return false if IPAddr.new(p_host).include?(addr)
            rescue IPAddr::InvalidAddressError
              next
            end
          end
        end
      }
      true
    end