Function pointers/delegates default args were stealth removed?

[Don Clugston]

On 27/08/12 16:16, Steven Schveighoffer wrote:
> On Sun, 26 Aug 2012 18:26:40 -0400, Manu <turkeyman at gmail.com> wrote:
>
>> I just updated to 2.60 and found errors throughout my code where function
>> pointers default args no longer work.
>> *Every single project* I've written in D, 5 projects, don't work anymore,
>> including my projects at work.
>
> OK, I've read all the posts on this, and this is what I think would
> solve the problem:
>
> 1. default parameters are part of the function pointer type, because a
> function pointer has a type.
> 2. The mangled name of the function that is assigned to that function
> pointer does *not* have default parameters mangled in.  Only the
> function pointer type has them.
> 3. Since the default parameters are part of the type, but not defined by
> the function it points to, you can use interchangeably functions of the
> same type which define default parameters or not (or define different
> ones).  The default parameters follow the function pointer variable.

This sounds like sloppy thinking.
I _think_ what you are saying is that there should be implicit 
conversions from one function pointer type, to any other that has the 
same basic declaration, but different default arguments.

But then you get problems with IFTI.
void foo( void function(int x), double) {}
void foo( void function(int x), int) {}

void function(int x = 10) bar;

foo(bar, 5); // fails -- ambiguous. Both overloads match with implicit 
conversions.


But really, it seems to me that this whole feature is just syntax sugar 
for one special case of currying.