anchor.diff:          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;
  
positive.code:           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 {
  
negative.code:                   mkfs.${fs.fsType} "${fs.device}"
                  fi
                fi
              '')}
  
              # Create missing swapfiles.
  