``fish_indent`` is used to indent a piece of fish code. ``fish_indent`` reads commands from standard input and outputs them to standard output or a specified file.
-``--ansi`` colorizes the output using ANSI escape sequences, appropriate for the current $TERM, using the colors defined in the environment (such as ``$fish_color_command``).
-``--html`` outputs HTML, which supports syntax highlighting if the appropriate CSS is defined. The CSS class names are the same as the variable names, such as ``fish_color_command``.
-``-D`` or ``--debug-stack-frames=DEBUG_LEVEL`` specify how many stack frames to display when debug messages are written. The default is zero. A value of 3 or 4 is usually sufficient to gain insight into how a given debug call was reached but you can specify a value up to 128.
-``--dump-parse-tree`` dumps information about the parsed statements to stderr. This is likely to be of interest only to people working on the fish source code.