help-internal {box} | R Documentation |
Helper functions for the help functionality
Description
help_topic_target
parses the expression being passed to the
help
function call to find the innermost module subset expression in
it.
find_env
acts similarly to find
, except that it
looks in the current environment’s parents rather than in the global
environment search list, it returns only one hit (or zero), and it returns
the environment rather than a character string.
call_help
invokes a help()
call expression for a package help
topic, finding the first help
function definition, ignoring the one
from this package.
Usage
help_topic_target(topic, caller)
find_env(name, caller)
call_help(call, caller)
Arguments
topic |
the unevaluated expression passed to |
caller |
the environment from which |
name |
the name to look for. |
call |
the patched |
Value
help_topic_target
returns a list of two elements containing
the innermost module of the help
call, as well as the name of the
object that’s the subject of the help
call. For help(a$b$c$d)
,
it returns list(c, quote(d))
.