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Please usecli for new projects.

crayon is still supported and will receive important bug fixes,but no new features.

Stylish terminal output in R

With crayon it is easy to add color to terminal output, create styles for notes, warnings, errors; and combine styles.

ANSI color support is automatically detected and used. Crayon was largelyinspired bychalk.

Stable version:

install.packages("crayon")

Development version:

pak::pak("r-lib/crayon")

Crayon defines several styles that can be combined. Each style in the listhas a corresponding function with the same name.

• reset
• bold
• blurred (usually calleddim, renamed to avoid name clash)
• italic (not widely supported)
• underline
• inverse
• hidden
• strikethrough (not widely supported)

• black
• red
• green
• yellow
• blue
• magenta
• cyan
• white
• silver (usually calledgray, renamed to avoid name clash)

• bgBlack
• bgRed
• bgGreen
• bgYellow
• bgBlue
• bgMagenta
• bgCyan
• bgWhite

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 easyto assemble strings 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'))

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$boldwarn<-magenta$underlinenote<-cyancat(error("Error: subscript out of bounds!\n"))cat(warn("Warning: shorter argument was recycled.\n"))cat(note("Note: no such directory.\n"))

Most modern terminals support the ANSI standard for 256 colors,and you can define new styles that make use of them. Themake_stylefunction defines a new style. It can handle R's built in color names(see the output ofcolors()) as well as RGB specifications via thergb() function. It automatically chooses the ANSI colors thatare closest to the specified R and RGB colors, and it also hasa fallback to terminals with 8 ANSI colors only.

ivory<- make_style("ivory")bgMaroon<- make_style("maroon",bg=TRUE)fancy<- combine_styles(ivory,bgMaroon)cat(fancy("This will have some fancy colors"),"\n")

MIT @ Gábor Csárdi