These are environment variables and options that uses may set, to modify the behavior of cli.
User facing environment variables
R_CLI_HYPERLINK_MODE
Set to posix to force generating POSIX compatible ANSI
hyperlinks. If not set, then RStudio compatible links are generated.
This is a temporary crutch until RStudio handles POSIX hyperlinks
correctly, and after that it will be removed.
ESS_BACKGROUND_MODE
Set this environment variable to light or
dark to indicate dark mode in Emacs. Once https://github.com/emacs-ess/ESS/pull/1178 is merged,
ESS will set this automatically.
R_CLI_DYNAMIC
Set to true, TRUE or True to
assume a dynamic terminal, that supports \r. Set to
anything else to assume a non-dynamic terminal. See
[is_dynamic_tty()].
User facing options
cli.ansi
Set to true, TRUE or True to
assume a terminal that supports ANSI control sequences. Set to anything
else to assume a non-ANSI terminal. See [is_ansi_tty()].
cli.condition_unicode_bullets
TRUE or FALSE to force turn on or off the
Unicode symbols when printing conditions. E.g. in
format_error(), format_warning(),
format_message() and also in cli_abort(),
cli_warn() and cli_inform().
cli.condition_width
Integer scalar (or Inf) to set the console width when
cli is formatting errors, warnings or messages in
format_error(), format_warning() and
format_message(). When formatting conditions this option
takes precedence over cli.width.
cli.default_handler
General handler function for all cli conditions. See https://cli.r-lib.org/articles/semantic-cli.html#cli-messages-1
cli.default_num_colors
Default number of ANSI colors. This value is used if the number of
colors is not already set by * the cli.num_colors option, *
the R_CLI_NUM_COLORS environment variable, * the
crayon.enabled and crayon.colors options, *
the NO_COLOR environment variable, * the
knitr.in.progress option, * a sink() call for
the stream.
You can also use this option if color support is detected correctly,
but you want to adjust the number of colors. E.g. * if
crayon.enabled is TRUE, but
crayon.colors is not, * in Emacs on Windows, * in
terminals.
See [num_ansi_colors()]. See also the cli.num_colors
option.
cli.dynamic
Set to TRUE to assume a dynamic terminal, that supports
\r. Set to anything else to assume a non-dynamic terminal.
See [is_dynamic_tty()].
cli.hide_cursor
Whether the cli status bar should try to hide the cursor on
terminals. Set the FALSE if the hidden cursor causes
issues.
cli.hyperlink
Set to true, TRUE or True to
tell cli that the terminal supports ANSI hyperlinks. Set to anything
else to assume no hyperlink support. See [style_hyperlink()].
cli.ignore_unknown_rstudio_theme
Set to TRUE to omit a warning for an unknown RStudio
theme in code_highlight().
cli.num_colors
Number of ANSI colors. See [num_ansi_colors()]. See also the
cli.default_num_colors option.
cli.progress_bar_style_unicode
Progress bar style on Unicode (UTF-8) consoles; See [cli_progress_styles()].
cli.progress_clear
Whether to clear terminated progress bar from the screen on dynamic terminals. See [cli_progress_bar()].
cli.progress_demo_live
Whether cli_progress_demo() should show a live demo, or
just record the progress bar frames.
cli.progress_format_download_nototal
Default format string for download progress bars with
unknown totals.
cli.progress_format_iterator_nototal
Default format string for iterator progress bars with
unknown total number of progress units.
cli.progress_format_tasks_nototal
Default format string for tasks progress bars with
unknown totals.
cli.progress_handlers_force
Progress handlers that will always be used, even if another handler was already selected. See [cli_progress_builtin_handlers()].
cli.progress_handlers_only
Progress handlers to force, ignoring handlers set in
cli.progress_handlers and
cli.progress_handlers_force. See
[cli_progress_builtin_handlers()].
cli.progress_say_args
Command line arguments for the say progress handlers.
See [cli_progress_builtin_handlers()].
cli.progress_say_command
External command to use in the say progress handler. See
[cli_progress_builtin_handlers()].
cli.progress_say_frequency
Minimum delay between say calls in the say
progress handler. say ignores very frequent updates, to
keep the speech comprehensible. See
[cli_progress_builtin_handlers()].
cli.progress_show_after
Delay before showing a progress bar, in seconds. Progress bars that finish before this delay are not shown at all. cli also shows progress bars that have more than 50% to go after half of this delay has passed.
cli.theme
Default cli theme, in addition to the built-in theme. This option in intended for the package developers. See [themes] and [start_app()].
cli.unicode
Whether to assume a Unicode terminal. If not set, then it is auto-detected. See [is_utf8_output()].