Latex and variables in plot label in R?

Question

How do I use variables in Latex expressions in R?

For example:

plot(X, Y, main=expression(R^2))

Will put R with a nice superscripted 2

Answer 1

Well this works...

call(':', quote(R^2), a)

though it feels a little hacky to me since it's using R's : operator, whereas you just want to stick some text on the end. Maybe there's a better way?