is.recursive              package:base              R Documentation

Is an Object Atomic or Recursive?

Description:

     `is.atomic' returns `TRUE' if `x' does not have a list structure
     and `FALSE' otherwise.

     `is.recursive' returns `TRUE' if `x' has a recursive (list-like)
     structure and `FALSE' otherwise.

Usage:

     is.atomic(x)
     is.recursive(x)

Arguments:

       x: object to be tested.

See Also:

     `is.list', `is.language', etc, and the `demo("is.things")'.

Examples:

     is.a.r <- function(x) c(is.atomic(x), is.recursive(x))

     is.a.r(c(a=1,b=3))# TRUE FALSE
     is.a.r(list())    # FALSE TRUE ??
     is.a.r(list(2))   # FALSE TRUE
     is.a.r(lm)        #   "
     is.a.r(y ~ x)     #   "
     is.a.r(expression(x+1))# should be F-T (not in 0.62.3!)

