The design of the statistical programming language R sits in a slightly uncomfortable place between the functional programming and object oriented paradigms. The upside is you get a lot of the expressive power of both programming paradigms. A downside of this is: the not always useful variability of the language’s list and object extraction operators.
Towards the end of our write-up Survive R we recommended using explicit environments with new.env(hash=TRUE,parent=emptyenv())
, assign()
and get()
to simulate mutable string-keyed maps for storing results. This advice rose out of frustration with the apparent inconsistency with the user facing R list operators. In this article we bite the bullet and discuss the R list operators a bit more clearly. Continue reading Selection in R