env_has() is a vectorised predicate that queries whether an
environment owns bindings personally (with
inherit set to
FALSE, the default), or sees them in its own environment or in
any of its parents (with
inherit = TRUE).
env_has(env = caller_env(), nms, inherit = FALSE)
A character vector of binding names for which to check existence.
Whether to look for bindings in the parent environments.
A named logical vector as long as