R exercise: Write your own version of exists(inherits = FALSE) (Hint: use ls()). Write a recursive version that behaves like inherits = TRUE. http://adv-r.had.co.nz/Environments.html

exists.r

exists <- function(name, env = parent.frame(), inherits = TRUE) {
  if (identical(env, emptyenv())) return(FALSE)
  
  if (name %in% ls(envir = env)) TRUE
  else if (inherits) exists(name, parent.env(env))
  else FALSE
}