Crayon defines several styles, that can be combined. Each style in the list
has a corresponding function with the same name.
Genaral styles
reset
bold
blurred (usually called ‘dim’, renamed to avoid name clash)
italic (not widely supported)
underline
inverse
hidden
strikethrough (not widely supported)
Text colors
black
red
green
yellow
blue
magenta
cyan
white
silver (usually called ‘gray’, renamed to avoid name clash)
Background colors
bgBlack
bgRed
bgGreen
bgYellow
bgBlue
bgMagenta
bgCyan
bgWhite
Styling
The styling functions take any number of character vectors as arguments,
and they concatenate and style them:
library(crayon)
cat(blue("Hello", "world!\n"))
Crayon defines the %+% string concatenation operator, to make it easy
to assemble stings with different styles.
cat("... to highlight the " %+% red("search term") %+%
" in a block of text\n")
Styles can be combined using the $ operator:
cat(yellow$bgMagenta$bold('Hello world!\n'))
See also combine_styles.
Styles can also be nested, and then inner style takes
precedence:
cat(green(
'I am a green line ' %+%
blue$underline$bold('with a blue substring') %+%
' that becomes green again!\n'
))
It is easy to define your own themes:
error <- red $ bold
warn <- magenta $ underline
note <- cyan
cat(error("Error: subscript out of bounds!\n"))
cat(warn("Warning: shorter argument was recycled.\n"))
cat(note("Note: no such directory.\n"))
See Also
make_style for using the 256 ANSI colors.
Examples
cat(blue("Hello", "world!"))
cat("... to highlight the " %+% red("search term") %+%
" in a block of text")
cat(yellow$bgMagenta$bold('Hello world!'))
cat(green(
'I am a green line ' %+%
blue$underline$bold('with a blue substring') %+%
' that becomes green again!'
))
error <- red $ bold
warn <- magenta $ underline
note <- cyan
cat(error("Error: subscript out of bounds!\n"))
cat(warn("Warning: shorter argument was recycled.\n"))
cat(note("Note: no such directory.\n"))