github/linguist — pull request #1208 by jkeirstead (2014-05-21 13:42:57+00:00)
Title: R documentation

R packages often include extension documentation with the `Rd` extension. For example, see [ggplot2](https://github.com/hadley/ggplot2). Presence of `Rd` files might help to increase the likelihood of a project being identified as pure R, rather than a mix of R and Rebol (which also uses the `.r` extension).