search for: _object_

.... A good motivating example is now ordered vs factor - I don't think you can say that ordered or factor have greater resolution than the other so: vec_c(factor("a"), ordered("a")) #> Error: No common type for factor and ordered This is not what you'd expect from an _object_ system since ordered is a subclass of factor. Hadley -- http://hadley.nz

Sorry, for j On Thu, May 1, 2008 at 1:16 PM, David Vandevoorde <daveed at vandevoorde.com> wrote: > > Another valid implementation of malloc is one that actually returns a > non-null pointer in this case, and for such an implementation, a valid > reduction is "int main() { return 1; }". That reduction is IMO not > only valid, but also defensible and maybe

I'd like to have two packages with S4 classes with the same name but different implementation. To that end I create a package tmpA with setClass("A", representation=representation( x="numeric"), sealed=TRUE) setClass("B", representation=representation( x="numeric")) B <- function(...)

On May 1, 2008, at 12:47 PM, David Greene wrote: > On Wednesday 30 April 2008 20:01, David Vandevoorde wrote: > >> Correct. It's an extreme form of garbage collection, I suppose ;-) >> >> (In theory, it can also be assumed to fail -- because an >> implementation is allowed to make any call to malloc fail -- though >> that's probably not useful.) >

...e variable somewhere that changed, but that variable isn't required by the standard, and a compiler may instead posit that for this very call to malloc, a separate heap is used.) There is (at least) a subtlety with that reasoning in C having to do with "lifetime": The allocated _object_ has a lifetime (7.20.3/1) that extends until deallocation. My view is that the storage only becomes an object when the pointer returned is bound to a typed pointer (7.20.3/1). If that's right, every instance of the particular malloc call can produce the same value; if not, we'd ne...

On Wed, 2008-04-30 at 18:26 -0400, David Vandevoorde wrote: > > Daveed: > > > > Good to know that I was looking at the correct section. I do not agree > > that your interpretation follows the as-if rule, because I do not > > agree > > with your interpretation of the C library specification of malloc(). > > > Before I go on, let me state that this is

>>>>> Hadley Wickham >>>>> on Wed, 8 Aug 2018 09:34:42 -0500 writes: >>>> Method dispatch for `vec_c()` is quite simple because >>>> associativity and commutativity mean that we can >>>> determine the output type only by considering a pair of >>>> inputs at a time. To this end, vctrs provides