Performs ls all the way up to a top-level environment (either
the parent of the global environment, the empty environment or a namespace
environment).
rls(env = parent.frame(), all.names = TRUE)environment to start the search at. Defaults to the
parent.frame. If a function is supplied, uses the environment
associated with the function.
Show all names, even those starting with .?
Defaults to TRUE, the opposite of ls