Basic format for command 'show':
    vitis-sl show [[-e][-v][--all-categories]] <input data> [options]

vitis-sl show --all-categories [--hidden] [--auto]
    The command displays a list of all created categories.
    The optional option --hidden enables the display of hidden categories.
    The optional option --auto enables the display of automatic categories.

vitis-sl show <category> [options]
    This command displays a list of files from the category.
    If the category is nested, the full path is spelled.
    Example:
        vitis-sl show "Disco 80's"

vitis-sl show [-e] <expression> [options]
    This command displays a list of files according to the expression
    with the operations of intersection, union, complement (subtraction).
    The '-e' flag is optional.
    Variants of the designation of operations:
        union:         u: +  ∪  ⋃
        intersection:  i: ∩  ⋂
        complement:    c: d: \\
    Grouping the parts of the expression is done using braces.
    All components of the expression (including brackets)
    are separated by spaces.
    Examples:
        vitis-sl show -e category1 u: category2 u: category3
            This command displays all files from three categories.
        vitis-sl show category1 + category2 ∪ category3
            This command does the same.
        vitis-sl show category1 i: { category2 u: category3 }
            This command unites two categories and crosses them with the first.

Flag '-n' is used to select one or a series of files.
If there is a number after the '-n' flag, one file will be displayed.
Also, after the -n flag, you can use an expression that lists the numbers
of the files you need and ranges of files using a dash,
separated by commas without spaces.
Examples:
    vitis-sl show Music -n 4-13,18,24-31
        Files from the 4th through the 13th inclusive, the 18th,
        and the 24th through the 31st inclusive are output.
    vitis-sl show Books -n 1
        The first book from the "Books" category will be displayed.

Flag --sort=<sorting> is used to specify the sorting type:
     --sort=extension - sort by file extension;
     --sort=name      - sort by file name (default);
     --sort=none      - without sorting;
     --sort=size      - sort by file size;
     --sort=time      - sort by file modification time;
     --sort=atime     - sort by file access time.

Flag '--categories' enables displaying all categories of output files.
Flag '--details' enables displaying file properties.
Flag '--fragment-info' enables the display of properties
    of pointers to fragments.
Flag '--hidden' enables the displaying of hidden files
    and hidden categories (with '--categories').
Flag '--ipaths' enables the display of URLs for network bookmarks.
Flag '--machine' (or '-m') prints a list of lies in quotation marks
    in a column with the disabling of color output and file numbers.
Flag '--no-colors' turns off the color output.
Flag '--no-numbers' disables the output of file numbers.
Flag '--paths' displays the full paths to the files.
Flag '--reverse' reverses the sort order.
Flag '--open' allows you to open files. With this flag,
    the options for the 'vitis-sl open' command are available.
    Details about 'vitis-sl open':
        vitis-sl open --help
Flag '--run' allows you to run files (if files are programs).
    With this flag, options are available for the 'vitis-sl run'.
    Details about 'vitis-sl run':
        vitis-sl run --help


vitis-sl show -v <category/file> [options]
    Displays the file available in vitis-sl.

Most of the above options apply to this command:
--categories, --details, --fragment-info, --hidden, --ipaths, --machine|-m,
--no-colors, --no-numbers, --open, --paths, --run.
Additional option '--number' allows you to specify the file number
from the list of files with duplicate names.
