getFromNamespace            package:utils            R Documentation

Utility functions for Developing Namespaces

Description:

     Utility functions to access and replace the non-exported functions
     in a namespace, for use in developing packages with namespaces.

Usage:

     getFromNamespace(x, ns, pos = -1, envir = as.environment(pos))

     assignInNamespace(x, value, ns, pos = -1,
                       envir = as.environment(pos))

     fixInNamespace(x, ns, pos = -1, envir = as.environment(pos), ...)

Arguments:

       x: an object name (given as a character string).

   value: an R object.

      ns: a namespace, or character string giving the namespace.

     pos: where to look for the object: see 'get'.

   envir: an alternative way to specify an environment to look in.

     ...: arguments to pass to the editor: see 'edit'.

Details:

     The namespace can be specified in several ways.  Using, for
     example, 'ns = "stats"' is the most direct, but a loaded package
     with a namespace can be specified via any of the methods used for
     'get': 'ns' can also be the environment printed as
     '<namespace:foo>'.

     'getFromNamespace' is similar to (but predates) the ':::'
     operator, but is more flexible in how the namespace is specified.

     'fixInNamespace' invokes 'edit' on the object named 'x' and
     assigns the revised object in place of the original object.  For
     compatibility with 'fix', 'x' can be unquoted.

Value:

     'getFromNamespace' returns the object found (or gives an error).

     'assignInNamespace' and 'fixInNamespace' are invoked for their
     side effect of changing the object in the namespace.

Note:

     'assignInNamespace' and 'fixInNamespace' change the copy in the
     namespace, but not any copies already exported from the namespace,
     in particular an object of that name in the package (if already
     attached) and any copies already imported into other namespaces.
     They are really intended to be used _only_ for objects which are
     not exported from the namespace.  They do attempt to alter a copy
     registered as an S3 method if one is found.

     They can only be used to change the values of objects in the
     namespace, not to create new objects.

See Also:

     'get', 'fix', 'getS3method'

Examples:

     getFromNamespace("findGeneric", "utils")
     ## Not run: 
     fixInNamespace("predict.ppr", "stats")
     stats:::predict.ppr
     getS3method("predict", "ppr")
     ## alternatively
     fixInNamespace("predict.ppr", pos = 3)
     fixInNamespace("predict.ppr", pos = "package:stats")
     ## End(Not run)

