w <- 2.5; x <- c(1,2); y <- "foo"; z <- TRUE; abc <- letters[1:3]
mode(w); length(w)
mode(x); length(x)
mode(y); length(y)
y[1]; y[2]             # not an error to ask for y[2]
mode(z); length(z)
abc
mode(abc); length(abc)
abc[3]
