The goal of styler is to provide non-invasive pretty-printing of R source code while adhering to the tidyverse formatting rules. styler can be customized to format code according to other style guides too.

The following online docs are available:

Installation

You can install the package from CRAN.

If you don’t use styler interactively (i.e. not from the R prompt or RStudio Addin), make sure you authorize {R.cache} once to set up a permanent cache. If you use it interactively, you will be asked to grant this permission once. See ?caching for details.

Or get the development version from GitHub:

# install.packages("remotes")
remotes::install_github("r-lib/styler")

API

You can style a simple character vector of code with style_text():

library("styler")
ugly_code <- "a=function( x){1+1}           "
style_text(ugly_code)
#> a <- function(x) {
#>   1 + 1
#> }

There are a few variants of style_text():

  • style_file() styles .R, .Rmd .Rnw and .Rprofile, files.

  • style_dir() styles all .R and/or .Rmd files in a directory.

  • style_pkg() styles the source files of an R package.

  • RStudio Addins for styling the active file, styling the current package and styling the highlighted code region.

Configuration

You can decide on the level of invasiveness with the scope argument. You can style:

  • just spaces.

  • spaces and indention.

  • spaces, indention and line breaks.

  • spaces, indention, line breaks and tokens.

ugly_code <- "a=function( x){1+1}           "
style_text(ugly_code, scope = "spaces")
#> a = function(x) {1 + 1}

Note that compared to the default used above scope = "tokens":

  • no line breaks were added.

  • <- was not replaced with =.

While spaces still got styled (around = in (x)).

This was just the tip of the iceberg. To learn more about customization options with the tidyverse style guide, see the help file for `tidyverse_style for a quick overview or the introductory vignette.

Features

Adaption of styler

styler functionality is made available through other tools, most notably

Further resources

  • The official web documentation of styler, containing various vignettes function documentation as well as a change-log.

  • Blog post about how you can customize styler without being an expert.

  • A tidyverse.org blog post introducing the functionality of styler and a follow-up post that introduces the new features since release 1.0.0.

  • The wiki of Google Summer of Code 2017 or the pkgdown page contain information related to the initial development phase during Google Summer of Code 2017.