> Stylish terminal output in R [](http://www.repostatus.org/#active) [](https://travis-ci.org/r-lib/crayon) [](https://ci.appveyor.com/project/gaborcsardi/crayon) [](http://cran.rstudio.com/web/packages/crayon/index.html) [](http://cran.r-project.org/web/packages/crayon/index.html) [](https://codecov.io/github/r-lib/crayon?branch=master) 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 largely inspired by [chalk](https://github.com/sindresorhus/chalk). ## Installation ```r devtools::install_github("r-lib/crayon") library(crayon) ``` ## Styles Crayon defines several styles, that can be combined. Each style in the list has a corresponding function with the same name. ### General 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` ### Screenshot on OSX  ## Usage The styling functions take any number of character vectors as arguments, and they concatenate and style them: ```r library(crayon) cat(blue("Hello", "world!\n")) ``` Crayon defines the `%+%` string concatenation operator, to make it easy to assemble stings with different styles. ```r cat("... to highlight the " %+% red("search term") %+% " in a block of text\n") ``` Styles can be combined using the `$` operator: ```r cat(yellow$bgMagenta$bold('Hello world!\n')) ``` Styles can also be nested, and then inner style takes precedence: ```r cat(green( 'I am a green line ' %+% blue$underline$bold('with a blue substring') %+% ' that becomes green again!\n' )) ``` It is easy to define your own themes: ```r 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")) ``` ## 256 colors Most modern terminals support the ANSI standard for 256 colors, and you can define new styles that make use of them. The `make_style` function defines a new style. It can handle R's built in color names (see the output of `colors()`), and also RGB specifications, via the `rgb()` function. It automatically chooses the ANSI colors that are closest to the specified R and RGB colors, and it also has a fallback to terminals with 8 ANSI colors only. ```r ivory <- make_style("ivory") bgMaroon <- make_style("maroon", bg = TRUE) fancy <- combine_styles(ivory, bgMaroon) cat(fancy("This will have some fancy colors"), "\n") ```  ## License MIT @ Gábor Csárdi