env_parent() returns the parent environment of
env if called
n = 1, the grandparent with
n = 2, etc.
env_tail() searches through the parents and returns the one
empty_env() as parent.
env_parents() returns the list of all parents, including the
empty environment. This list is named using
See the section on inheritance in
env_parent(env = caller_env(), n = 1) env_tail(env = caller_env(), last = global_env(), sentinel = NULL) env_parents(env = caller_env(), last = global_env())
The number of generations to go up.
The environment at which to stop. Defaults to the global environment. The empty environment is always a stopping condition so it is safe to leave the default even when taking the tail or the parents of an environment on the search path.
This argument is soft-deprecated, please use
An environment for
env_tail(), a list
of environments for
sentinel argument of
env_tail() has been deprecated in
rlang 0.2.0 and renamed to
# Get the parent environment with env_parent(): env_parent(global_env())#> <environment: 0x5d0bee8> #> attr(,"name") #>  "devtools_shims"# Or the tail environment with env_tail(): env_tail(global_env())#> <environment: base># By default, env_parent() returns the parent environment of the # current evaluation frame. If called at top-level (the global # frame), the following two expressions are equivalent: env_parent()#> <environment: 0x310c408>env_parent(base_env())#> <environment: R_EmptyEnv># This default is more handy when called within a function. In this # case, the enclosure environment of the function is returned # (since it is the parent of the evaluation frame): enclos_env <- env() fn <- set_env(function() env_parent(), enclos_env) identical(enclos_env, fn())#>  TRUE