anchor.diff:            type = types.string;
             merge = pkgs.lib.concatStringsSep ",";
             description = "Options used to mount the file system.";
  -        };
  -
  -        autocreate = mkOption {
  -          default = false;
  -          type = types.bool;
  -          description = ''
  -            Automatically create the mount point defined in
  -            <option>fileSystems.*.mountPoint</option>.
  -          '';
           };
   
           autoFormat = mkOption {
  
positive.code:         specify a volume label (<literal>label</literal>) for file
          systems that support it, such as ext2/ext3 (see <command>mke2fs
          -L</command>).
  
          <literal>autocreate</literal> forces <literal>mountPoint</literal> to be created with
          <command>mkdir -p</command> .
        '';
  
        type = types.list types.optionSet;
  
negative.code:                   mkfs.${fs.fsType} "${fs.device}"
                  fi
                fi
              '')}
  
              # Create missing swapfiles.
  