Thank you Brian, > setReplaceMethod() is just syntactic sugar for setting an S4 method on a > replacement function (read the function definition to see so). You can > set S3 replacement methods, and the S4 mechanism just piggy-backs on that.
So I understand that setReplaceMethod will not help. > I think the conceptual problem is that the assignment operator does not > actually do any copying: it creates a binding of a symbol to a value. > Any copying which occurs happens when the value is (potentially) changed. I would be even happier if the cloning would only occur on any attempt to change the external pointer / proxy-object. > There is no provision for that to depend on the class (rather than the > type) of the object. Mh, unless the internal copying mechanism would call a clone generic for non-atomic objects > Since external pointers are never duplicated, you > ought to be able to take advantage of that to design the copying semantics > you want. How that? How do I know that any user has assigned/modified the external pointer (or a proxy object containing the external pointer) such that I can invoke the cloning? Best regards Jens Oehlschlägel -- ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
