On Jul 25, 2013, at 12:08 , Matt Neuburg wrote:
> Well, and discussions of the issue often fail to take into account the
> problem of distinguishing the context on an instance-by-instance basis.
> Passing "self" as a context does that, obviously; but the "static void*"
> trick does not (there
Well, and discussions of the issue often fail to take into account the problem
of distinguishing the context on an instance-by-instance basis. Passing "self"
as a context does that, obviously; but the "static void*" trick does not (there
is one storage per class, not per instance of that class).
On Jul 25, 2013, at 07:20 , Matt Neuburg wrote:
> storage of the value passed as context:(void*), not just in addObserver:, but
> in general
I think I'd take this in a different direction. In *all* of these scenarios the
context parameter is a mechanism for passing a pointer to a data structur
On Jul 25, 2013, at 8:50 AM, Matt Neuburg wrote:
> But surely that can't work, since you set up the call once but you can get
> called back many times - or am I misunderstanding? m.
Sorry, that depends on the callback, and I was thinking specifically of
one-shot ones. (Think of beginSheetModal
Well the second two examples of those are rather different from the first.
In the case of sortedArrayUsingFunction:context: and beginAnimations:context:
the context is there really as an opaque pointer to pass data into the
function. That pattern of function + was the pre-blocks way to pass co
On Jul 25, 2013, at 7:33 AM, Scott Ribe wrote:
> If you alloc an object per callback setup, right where you set up the
> callback, and release it in the callback, you're safe--and that's a very
> common pattern I think
But surely that can't work, since you set up the call once but you can get
On Jul 25, 2013, at 8:20 AM, Matt Neuburg wrote:
> Is this the only safe/sensible storage? Could it be an actual object, cast
> back and forth between id and void*? Could it be stored as an ivar? Thx as
> always - m.
No, of course, and yes ;-)
Now the static idiom you mentioned is nice in tha
I'd like to hear some arguments / opinions / essays on storage of the value
passed as context:(void*), not just in addObserver:, but in general - so,
including things like beginAnimations:context: and
sortedArrayUsingFunction:context:.
Must it always be an external variable? Must it always be s
