The progress handler(s) to use can be selected with global options.

cli_progress_builtin_handlers()

Value

cli_progress_builtin_handlers() returns the names of the currently supported progress handlers.

Details

There are three options that specify which handlers will be selected, but most of the time you only need to use one of them. You can set these options to a character vector, the names of the built-in cli handlers you want to use:

  • If cli.progress_handlers_only is set, then these handlers are used, without considering others and without checking if they are able to handle a progress bar. This option is mainly intended for testing purposes.

  • The handlers named in cli.progress_handlers are checked if they are able to handle the progress bar, and from the ones that are, the first one is selected. This is usually the option that the end use would want to set.

  • The handlers named in cli.progress_handlers_force are always appended to the ones selected via cli.progress_handlers. This option is useful to add an additional handler, e.g. a logger that writes to a file.

The built-in progress handlers

cli

Use cli's internal status bar, the last line of the screen, to show the progress bar. This handler is always able to handle all progress bars.

logger

Log progress updates to the screen, with one line for each update and with time stamps. This handler is always able to handle all progress bars.

progressr

Use the progressr package to create progress bars. This handler is always able to handle all progress bars. (The progressr package needs to be installed.)

rstudio

Use RStudio's job panel to show the progress bars. This handler is available at the RStudio console, in recent versions of RStudio.

say

Use the macOS say command to announce progress events in speech (type man say on a terminal for more info). Set the cli.progress_say_frequency option to set the minimum delay between say invocations, the default is three seconds. This handler is available on macOS, if the say command is on the path.

The external command and its arguments can be configured with options:

  • cli_progress_say_args: command line arguments, e.g. you can use this to select a voice on macOS,

  • cli_progress_say_command: external command to run,

  • cli_progress_say_frequency: wait at least this many seconds between calling the external command.

shiny

Use shiny's progress bars. This handler is available if a shiny app is running.