Things that make writing a clean binding system more difficult

[Manu via Digitalmars-d]

On 29 July 2016 at 07:34, Steven Schveighoffer via Digitalmars-d
<digitalmars-d at puremagic.com> wrote:
> On 7/28/16 4:16 PM, Jonathan M Davis via Digitalmars-d wrote:
>>
>> On Thursday, July 28, 2016 01:49:35 Walter Bright via Digitalmars-d wrote:
>>>
>>> On 7/28/2016 1:33 AM, Ethan Watson wrote:
>>>>
>>>> 1) Declaring a function pointer with a ref return value can't be done
>>>> without workarounds.
>>>>
>>>> Try compiling this:
>>>>
>>>> ref int function( int, int ) functionPointer;
>>>>
>>>> It won't let you, because only parameters and for loop symbols can be
>>>> ref
>>>> types. Despite the fact that I intend the function pointer to be of a
>>>> kind that returns a ref int, I can't declare that easily. Easy, declare
>>>> an alias, right?
>>>>
>>>> alias RefFunctionPointer = ref int function( int, int );
>>>
>>>
>>> C/C++ have essentially the same problem, if you want to declare a
>>> function
>>> pointer parameter that has different linkage.
>>>
>>> The trouble is there's an ambiguity in the grammar. I don't really have
>>> anything better than the two step process you outlined.
>>
>>
>> Well, if we decided to make parens with ref legal, then we could make it
>> work. e.g.
>>
>> ref(int) function(int, int) functionPointer;
>>
>> Now, I don't know of any other case where you'd actually use parens with
>> ref
>> if it were legal, but it would solve this particular case if we wanted to
>> provide a way around the ambiguity.
>
>
> No, because that implies a type-modifier. ref does not modify the type at
> all, it just specifies the storage class.

Ah yes, one of the most fundamental and terrible mistake in D ;)