Menu
How do people learn about giving an R package a namespace? I find the documention in "R Extensions" fine, but I don't really get what is happening when a variable is imported or exported - I need a dummy's guide to these directives.
How do you decide what is exported? Is it just everything that really shouldn't required the pkg:::var syntax? What about imports?
Do imports make it easier to ensure that your use of other package functions doesn't get confused when function names overlap?
Are there special considerations for S4 classes?
Packages that I'm familiar with that use namespaces such as sp and rgdal are quite complicated - are there simple examples that could make things clearer?
972
A dependency is a code that your package needs to run. Dependencies are managed by two files. The DESCRIPTION manages dependencies at the package level; i.e. what packages needs to be installed for your package to work. R has a rich set of ways to describe different types of dependencies.
roxygen2 dynamically inspects the objects that it's documenting, so it can automatically add data that you'd otherwise have to write by hand. It abstracts over the differences in documenting S3 and S4 methods, generics and classes, so you need to learn fewer details.
I have a start on an answer on the devtools wiki: http://adv-r.had.co.nz/Namespaces.html
146
Few years later here....
I consolidated findings from Chambers, other StackOverflow posts, and lots of tinkering in R: http://blog.obeautifulcode.com/R/How-R-Searches-And-Finds-Stuff/
This is less about implementing NAMESPACE/IMPORTS/DEPENDS and more about the purpose of these structures. Answers some of your questions.
45
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
