how to get a primitive function object
If I understand properly, you want '<-' to be a generic function, which it currently isn't. There may be a way to fake that (I can't think of any). But I'm wondering if you should rethink what you want. The only reason that I can think of that you would want to change '<-' is because of some extra side effect that you want to happen. That is not in the spirit of R. Patrick Burns patrick at burns-stat.com +44 (0)20 8525 0696 http://www.burns-stat.com (home of "The R Inferno" and "A Guide for the Unwilling S User")
Yi Zhang wrote:
i was sort-of joking, though it's a real option if you want it.
but seriously, there's no reason for the &%#* lamenting:
x <- 1
'<-' = function(x,y) 0
x <- 2
# 0
.Primitive('<-')(x,2)
x
# 2
base::'<-'(x, 3)
x
# 3
base::'<-'('<-', base::'<-')
x <- 4
x
# 4
vQ
I'm still not sure if this can help solve my problem. If I want to
overwrite the `<-` operator for a particular type of objects, but
preserve its effect for other regular objects (in other words, if I do
x<-5 with my new <-, x will be 5 and nothing strange happens), then
what should I put in the [ ] below?
old <- `<-`
old(`<-`, function(x, value){
if (value is my type) do something
[ ] # to bind the object value to symbol x: no matter what you do
here, the binding/assignment is local within this function?!
})
Hope I have made myself clear. Thanks,