Is there an easier way to access attributes of a class in R, can I use dot notation?

Question

I have created an object in R that contains several attributes. How can I easily access them?

I can do:

attr(x, attributeName)

or:

Answer 1

attributes() returns a named list. I'd call it once and store them, then access via names. There is no point repeatedly calling either attr() or attributes() if you don't have to.

x <- 1:10
attr(x, "foo") <- "a"
attr(x, "bar") <- "b"
(features <- attributes(x))

which gives:

R> (features <- attributes(x))
$foo
[1] "a"

$bar
[1] "b"

then access in the usual way

R> features["foo"]
$foo
[1] "a"

R> features$foo
[1] "a"