cli has a number of functions to color and style text at the command line. They provide a mode modern interface than the crayon package.

## Usage

bg_black(...)

bg_blue(...)

bg_cyan(...)

bg_green(...)

bg_magenta(...)

bg_red(...)

bg_white(...)

bg_yellow(...)

bg_none(...)

bg_br_black(...)

bg_br_blue(...)

bg_br_cyan(...)

bg_br_green(...)

bg_br_magenta(...)

bg_br_red(...)

bg_br_white(...)

bg_br_yellow(...)

col_black(...)

col_blue(...)

col_cyan(...)

col_green(...)

col_magenta(...)

col_red(...)

col_white(...)

col_yellow(...)

col_grey(...)

col_silver(...)

col_none(...)

col_br_black(...)

col_br_blue(...)

col_br_cyan(...)

col_br_green(...)

col_br_magenta(...)

col_br_red(...)

col_br_white(...)

col_br_yellow(...)

style_dim(...)

style_blurred(...)

style_bold(...)

style_hidden(...)

style_inverse(...)

style_italic(...)

style_reset(...)

style_strikethrough(...)

style_underline(...)

style_no_bold(...)

style_no_blurred(...)

style_no_dim(...)

style_no_italic(...)

style_no_underline(...)

style_no_inverse(...)

style_no_hidden(...)

style_no_strikethrough(...)

style_no_color(...)

style_no_bg_color(...)

## Arguments

...

Character strings, they will be pasted together with paste0(), before applying the style function.

## Value

An ANSI string (class cli_ansi_string), that contains ANSI sequences, if the current platform supports them. You can simply use cat() to print them to the terminal.

## Details

The col_* functions change the (foreground) color to the text. These are the eight original ANSI colors. Note that in some terminals, they might actually look differently, as terminals have their own settings for how to show them. col_none() is the default color, this is useful in a substring of a colored string.

The col_br_* functions are bright versions of the eight ANSI colors. Note that on some terminal configurations and themes they might be the same as the non-bright colors.

The bg_* functions change the background color of the text. These are the eight original ANSI background colors. These, too, can vary in appearance, depending on terminal settings. bg_none() the the default background color, this is useful in a substring of a background-colored string.

The bg_br_* functions are the bright versions of the eight ANSI background colors. Note that on some terminal configurations and themes they might be the same as the non-bright colors.

The style_* functions apply other styling to the text. The currently supported styling functions are:

• style_reset() to remove any style, including color,

• style_bold() for boldface / strong text, although some terminals show a bright, high intensity text instead,

• style_dim() (or style_blurred() reduced intensity text.

• style_italic() (not widely supported).

• style_underline(),

• style_inverse(),

• style_hidden(),

• style_strikethrough() (not widely supported).

The style functions take any number of character vectors as arguments, and they concatenate them using paste0() before adding the style.

Styles can also be nested, and then inner style takes precedence, see examples below.

Sometimes you want to revert back to the default text color, in the middle of colored text, or you want to have a normal font in the middle of italic text. You can use the style_no_* functions for this. Every style_*() function has a style_no_*() pair, which defends its argument from taking on the style. See examples below.

Other ANSI styling: combine_ansi_styles(), make_ansi_style(), num_ansi_colors()

## Examples

col_blue("Hello ", "world!")
#> <cli_ansi_string>
#> [1] Hello world!
cat(col_blue("Hello ", "world!"))
#> Hello world!

cat("... to highlight the", col_red("search term"),
"in a block of text\n")
#> ... to highlight the search term in a block of text

## Style stack properly
cat(col_green(
"I am a green line ",
col_blue(style_underline(style_bold("with a blue substring"))),
" that becomes green again!"
))
#> I am a green line with a blue substring that becomes green again!

error <- combine_ansi_styles("red", "bold")
warn <- combine_ansi_styles("magenta", "underline")
note <- col_cyan
cat(error("Error: subscript out of bounds!\n"))
#> Error: subscript out of bounds!
#>
cat(warn("Warning: shorter argument was recycled.\n"))
#> Warning: shorter argument was recycled.
#>
cat(note("Note: no such directory.\n"))
#> Note: no such directory.
#>

# style_no_* functions, note that the color is not removed
style_italic(col_green(paste0(
"italic before, ",
style_no_italic("normal here, "),
"italic after"
)))
#> <cli_ansi_string>
#> [1] italic before, normal here, italic after

# avoiding  color for substring
style_italic(col_red(paste(
"red before",
col_none("not red between"),
"red after"
)))
#> <cli_ansi_string>
#> [1] red before not red between red after