mpaulacaldas / reprex

Render bits of R code for sharing, e.g., on GitHub or StackOverflow.

reprex

Overview

Prepare reprexes for posting to GitHub issues, StackOverflow, or Slack snippets. What is a reprex? It’s a reproducible example, as coined by Romain Francois.

Given R code on the clipboard, selected in RStudio, as an expression (quoted or not), or in a file …

• run it via rmarkdown::render(),
• with deliberate choices re: arguments and setup chunk.

Get resulting runnable code + output as

• Markdown, suitable for GitHub or Stack Overflow, or as
• R code, augmented with commented output.

Result is returned invisibly, placed on the clipboard, and written to a file. Preview an HTML version in RStudio viewer or default browser.

Installation

Install from CRAN:

install.packages("reprex")

or get a development version from GitHub:

devtools::install_github("tidyverse/reprex")

On Linux, you probably want to install xclip or xsel, so reprex can access the X11 clipboard. This is ‘nice to have’, but not mandatory. The usual sudo apt-get install or sudo yum install installation methods should work for both xclip and xsel.

Usage

Let’s say you copy this code onto your clipboard:

(y <- 1:4)
mean(y)

Then call reprex(), where the default target venue is GitHub:

reprex()

A nicely rendered HTML preview will display in RStudio’s Viewer (if you’re in RStudio) or your default browser otherwise.

The relevant bit of CommonMark Markdown is ready to be pasted from your clipboard:

``` r
(y <- 1:4)
#> [1] 1 2 3 4
mean(y)
#> [1] 2.5
```

Here’s what that Markdown would look like rendered in a GitHub issue:

(y <- 1:4)
#> [1] 1 2 3 4
mean(y)
#> [1] 2.5

Anyone else can copy, paste, and run this immediately.

In addition to GitHub, this markdown also works on Stack Overflow and Discourse. Those venues can be formally requested via venue = "so" and venue = "ds", but they are just aliases for venue = "gh".

Instead of reading from the clipboard, you can:

• reprex(mean(rnorm(10))) to get code from expression.

• reprex(input = "mean(rnorm(10))\n") gets code from character vector (detected via length or terminating newline). Leading prompts are stripped from input source: reprex(input = "> median(1:3)\n") produces same output as reprex(input = "median(1:3)\n")

• reprex(input = "my_reprex.R") gets code from file

• Use one of the RStudio add-ins to use the selected text or current file.

But wait, there’s more!

• Get a runnable R script, augmented with commented output, with reprex(..., venue = "R"). This is useful for Slack, email, etc.

• Get html with reprex(..., venue = "html"). Useful for sites that don't support markdown.

• Prepare rendered, syntax-highlighted code snippets to paste into Keynote or PowerPoint, with reprex(..., venue = "rtf"). This feature is still experimental; see the associated article for more.

• By default, figures are uploaded to imgur.com and the resulting URL is dropped into an inline image tag.

• Use the outfile argument to control where results are left behind. Use outfile = NA to work in current working directory.

• Append session info via reprex(..., si = TRUE).

• Get clean, runnable code from wild-caught reprexes with

  • reprex_invert() = the opposite of reprex()
  • reprex_clean(), e.g. when you copy/paste from GitHub or Stack Overflow
  • reprex_rescue(), when you’re dealing with copy/paste from R Console

Please note that the reprex project is released with a Contributor Code of Conduct. By contributing to this project, you agree to abide by its terms.