Taking a function or delegate as argument.

[simendsjo]

On 10.01.2012 15:53, Jacob Carlborg wrote:
> On 2012-01-10 14:48, simendsjo wrote:
>> On 10.01.2012 14:43, Mike Parker wrote:
>>> On 1/10/2012 10:05 PM, simendsjo wrote:
>>>> If I want to have a method taking a callback function, I have to
>>>> specify
>>>> if it should take a function or delegate even if I don't really care.
>>>> What's the best way to accept either? I cannot see any wrapper for
>>>> something like this in std.typecons.
>>>
>>> The simple way:
>>>
>>> void callback(int i, void delegate(int) dg)
>>> {
>>> dg(i);
>>> }
>>>
>>> void callback(int i, void function(int) fn)
>>> {
>>> void wrap(int j)
>>> {
>>> function(j);
>>> }
>>> callback(i, &wrap);
>>> }
>>
>> Yeah, but a bit tedious.. I found toDelegate:
>> http://dlang.org/phobos/std_functional.html#toDelegate
>
> Or make it a template parameter and check if it's callable using
> std.traits.isCallable.
>

Like this?
void callback(F)(int i, F fn) if(isCallable!F) {
   fn(i);
}

.. but then the parameters wouldn't be documented.