GClosure: The GClosure structure
Description
Basically, a GClosure is a transparent-type that represents an R function.Usage
toRGClosure(c_closure)
Value
an R closure with an extra ref attribute holding the original external reference
Details
When an API function requests a GClosure as a parameter, the user may pass any R function OR
an R object of class GClosure that is returned by certain API functions.
A GClosure represents an external object and thus inherits from RGtkObject.
The external GClosure objects may be coerced by the function toRGClosure
to an R closure. This means that you can effectively invoke external closures
(which may be implemented in C or R) in the same way as R functions.