anchor.diff:            The total size for caches.
   
             This can be a percentage, expressed with a fraction sign or as a
  -          decimal-point number, or any bytes-based unit. For example, "25%",
  -          "0.25" both represent 25% of the available system memory. The values
  -          "1000000000" and "1GB" both represent 1 gigabyte of memory.
  +          decimal-point number, or any bytes-based unit. For example,
  +          <literal>"25%"</literal>, <literal>"0.25"</literal> both represent
  +          25% of the available system memory. The values
  +          <literal>"1000000000"</literal> and <literal>"1GB"</literal> both
  +          represent 1 gigabyte of memory.
  +
           '';
         };
   
  
positive.code:       };
  
        port = mkOption {
          type = types.int;
          default = defaultPort;
          description = "Port to bind to for ${descr}";
        };
  
negative.code:           like datacenter.  The tiers and order must be the same on all nodes.
            Including more tiers is better than including fewer. For example:
  
            <literal>
                country=us,region=us-west,datacenter=us-west-1b,rack=12
                country=ca,region=ca-east,datacenter=ca-east-2,rack=4
  
                planet=earth,province=manitoba,colo=secondary,power=3
            </literal>
          '';
        };
  
  