| ns-lowlev {base} | R Documentation |
Low Level Name Space Support Functions
Description
Low level name space support functions.
Usage
attachNamespace(ns, pos = 2)
loadNamespace(package, lib.loc = NULL,
keep.source = getOption("keep.source.pkgs"))
loadedNamespaces()
unloadNamespace(ns)
Arguments
ns |
string or namespace object. |
pos |
integer specifying position to attach. |
package |
string naming the package/name space to load. |
lib.loc |
character vector specifying library search path. |
keep.source |
logical specifying whether to retain source. |
Details
The functions loadNamespace and attachNamespace are
usually called implicitly when library is used to load a name
space and any imports needed. However it may be useful to call
these functions directly at times.
loadNamespace loads the specified name space and registers it in
an internal data base. A request to load a name space that is already
loaded has no effect. The arguments have the same meaning as the
corresponding arguments to library. After loading,
loadNamespace looks for a hook function named .onLoad as
an internal variable in the name space (it should not be exported).
This function is called with the same arguments as
.First.lib.
loadNamespace does not attach the name space it loads to the
search path. attachNamespace can be used to attach a frame
containing the exported values of a name space to the search path.
The hook function .onAttach is run after the name space
exports are attached, but this is not likely to be useful. Shared
library loading and setting of options should be handled at load
time by the .onLoad hook.
loadedNamespaces returns a character vector of the names of
the loaded name spaces. unloadNamespace can be used to force
a name space to be unloaded. An error is signaled if the name space
is imported by other loaded name spaces. If defined, a hook
function .onUnload, analogous to .Last.lib, is run
after removing the name space from the internal registry.
Author(s)
Luke Tierney