Does the ternary operator exist in R?

Question

As the question asks, is there a control sequence in R similar to C\'s ternary operator? If so, how do you use it? Thanks!

Answer 1

Just as a prank, you can redefine the ? operator to (almost) work like the ternary operator (THIS IS A BAD IDEA):

`?` <- function(x, y) { y <-substitute(y); if(x) eval(y[[2]], parent.frame()) else eval(y[[3]], parent.frame()) }

x <- 1:3
length(x) ? (x*2) : 0
x <- numeric(0)
length(x) ? (x*2) : 0

for(i in 1:5) cat(i, (i %% 2) ? "Odd\n" : "Even\n")

... But you need to put the expressions in parentheses because the default precedence isn't like in C.

Just remember to restore the old help function when you're done playing:

rm(`?`)