Various aspects of the condition messages displayed by abort(), warn(), and inform() can be customised using options from the cli package.
By default, bulleted lists are prefixed with unicode symbols:
rlang::abort(c( "The error message.", "*" = "Regular bullet.", "i" = "Informative bullet.", "x" = "Cross bullet.", "v" = "Victory bullet.", ">" = "Arrow bullet." )) #> Error: #> ! The error message. #> <U+2022> Regular bullet. #> <U+2139> Informative bullet. #> <U+2716> Cross bullet. #> <U+2714> Victory bullet. #> <U+2192> Arrow bullet.
Set this option to use simple letters instead:
options(cli.condition_unicode_bullets = FALSE)rlang::abort(c( "The error message.", "*" = "Regular bullet.", "i" = "Informative bullet.", "x" = "Cross bullet.", "v" = "Victory bullet.", ">" = "Arrow bullet." )) #> Error: #> ! The error message. #> * Regular bullet. #> i Informative bullet. #> x Cross bullet. #> v Victory bullet. #> > Arrow bullet.
You can specify what symbol to use for each type of bullet through your cli user theme. For instance, here is how to uniformly use * for all bullet kinds:
options(cli.user_theme = list( ".cli_rlang .bullet-*" = list(before = "* "), ".cli_rlang .bullet-i" = list(before = "* "), ".cli_rlang .bullet-x" = list(before = "* "), ".cli_rlang .bullet-v" = list(before = "* "), ".cli_rlang .bullet->" = list(before = "* ") ))rlang::abort(c( "The error message.", "*" = "Regular bullet.", "i" = "Informative bullet.", "x" = "Cross bullet.", "v" = "Victory bullet.", ">" = "Arrow bullet." )) #> Error: #> ! The error message. #> * Regular bullet. #> * Informative bullet. #> * Cross bullet. #> * Victory bullet. #> * Arrow bullet.
If you want all the bullets to be the same, including the leading bullet, you can achieve this using the bullet class:
options(cli.user_theme = list( ".cli_rlang .bullet" = list(before = "* ") ))rlang::abort(c( "The error message.", "*" = "Regular bullet.", "i" = "Informative bullet.", "x" = "Cross bullet.", "v" = "Victory bullet.", ">" = "Arrow bullet." )) #> Error: #> * The error message. #> * Regular bullet. #> * Informative bullet. #> * Cross bullet. #> * Victory bullet. #> * Arrow bullet.
When called inside a function, abort() displays the function call to help contextualise the error:
splash <- function() {
abort("Can't splash without water.")
}splash()
#> Error in `splash()`:
#> ! Can't splash without water.
The call is formatted with cli as a code element. This is not visible in the manual, but code text is formatted with a highlighted background colour by default. When this can be reliably detected, that background colour is different depending on whether you're using a light or dark theme.
You can override the colour of code elements in your cli theme. Here is my personal configuration that fits well with the colour theme I currently use in my IDE:
options(cli.user_theme = list(
span.code = list(
"background-color" = "#3B4252",
color = "#E5E9F0"
)
))