# R: Low Level Name Space Support Functions

ns-lowlev {base} | R Documentation

## Low Level Name Space Support Functions

### Description

Low level name space support functions.

### Usage

    loadingNamespaceInfo()
    saveNamespaceImage(package, rdafile, lib.loc = NULL,
                       keep.source = getOption("keep.source.pkgs"),
                       compress = TRUE)

### Arguments

`package` | string naming the package/name space to load.
`rdafile` | name of file to save to.
`lib.loc` | character vector specifying library search path.
`keep.source` | logical specifying whether to retain source.
`compress` | option passed to `save`.

### 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`. Partial loading is used to support installation with the --save option.

`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.

`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` is run before removing the name space from the internal registry. `unloadNamespace` will first `detach` a package of the same name if one is on the path, thereby running a `.Last.lib` function in the package if one is exported.

`loadingNamespaceInfo` returns a list of the arguments that would be passed to `.onLoad` when a name space is being loaded. An error is signaled of a name space is not currently being loaded.

`saveNamespaceImage` is used to save name space images for packages installed with --save.

### Author(s)

Luke Tierney

[Package base version 2.6.0 Index]