Function pointers/delegates default args were stealth removed?

[Jonathan M Davis]

On Monday, August 27, 2012 11:38:52 Manu wrote:
> On 27 August 2012 11:12, Jonathan M Davis <jmdavisProg at gmx.com> wrote:
> > and it makes no sense to use them with function pointers or function
> > literals.
> 
> If that were true, we wouldn't be having this discussion.

You can't possibly really be using these functions with default arguments 
unless you're not really using them like function pointers, otherwise you 
wouldn't have been using the default arguments in the first place. Sure, you 
could have something like

auto func = (string a = "hello") { return a; }

and then call it with one argument or no argument, but that's only because the 
function is completely local, and you could just as easily do

string func(string a = "hello") { return a; }

and get the same thing. As soon as you've really used it as a function pointer 
rather than a local function, you've lost the default argument.

Default arguments just do not make sense with function pointers, because they 
don't follow the function pointer, because it's a _pointer_ and has no 
knowledge of what it's pointing to. It's only at the declaration point of the 
function that the default argument exists, and that has _nothing_ to do with 
the function pointer. You might as well ask a reference of type Object what 
the arguments used to construct the derived class that it actually refers to 
were as expect a function pointer to have any clue about default arguments to 
the function that it points to.

- Jonathan M Davis