findNextMethod {RNeXML} | R Documentation |
Finds the method that callNextMethod() should chain to
Description
Attempts to find the "next" method in the inheritance chain. This would
(ideally) be the method that methods::callNextMethod()
would chain to,
as a result of the method methods::addNextMethod()
would find (and return
in the nextMethod
slot of the MethodWithNext
object). Hence, in theory one shouldn't ever need this, but unfortunately
addNextMethod()
is broken (and errors out) if one of the classes in the
signature name-clashes with an S4 class defined in another package that is
loaded.
Usage
findNextMethod(method, f = NULL, envir = topenv())
Arguments
method |
|
f |
|
envir |
the environment in which to find the method |
Details
The next method will be determined by the S4 inheritance chain. However,
this function will walk only the inheritance chain of those arguments in
the signature that are defined in the package of the generic method from
which this function was invoked (directly or indirectly). If there are
no such parameters in the signature, or if there is more than one,
finding the next method is handed off to methods::addNextMethod()
.
Value
a MethodDefinition
object that is the next method in the
chain by inheritance
Note
In theory a class name clash between packages shouldn't be a problem
because class names can be namespaced, and the MethodDefinition
object passed to addNextMethod()
has all the necessary namespace
information. Hopefully, at some point this gets fixed in R, and then we
don't need this anymore.