R Packages, 2nd Edition

Chapter 1. The Whole Game

Spoiler alert!

This chapter runs through the development of a small toy package. It’s meant to paint the Big Picture and suggest a workflow, before we descend into the detailed treatment of the key components of an R package.

To keep the pace brisk, we exploit the modern conveniences in the devtools package and the RStudio IDE. In later chapters, we are more explicit about what those helpers are doing for us.

This chapter is self-contained, in that completing the exercise is not a strict requirement to continue with the rest of the book; however, we strongly suggest you follow along and create this toy package with us.

Load devtools and Friends

You can initiate your new package from any active R session. You don’t need to worry about whether you’re in an existing or new project. The functions we use ensure that we create a new clean project for the package.

Load the devtools package, which is the public face of a set of packages that support various aspects of package development. The most obvious of these is the usethis package, which you’ll see is also being loaded:

library(devtools)
#> Loading required package: usethis

Do you have an old version of devtools? Compare your version against ours and upgrade if necessary:

packageVersion("devtools")
#> [1] '2.4.5'

Toy Package: regexcite

To help walk you through the process, we use various functions from devtools to build a small toy package from scratch, with features commonly seen in released packages: ...