Anonymous function syntax

[Jacob Carlborg]

On 2011-09-23 08:42, Daniel Murphy wrote:
> "Jacob Carlborg"<doob at me.com>  wrote in message
> news:j5h98l$ors$1 at digitalmars.com...
>> What I'm saying is that you can ignore the returned value of a delegate
>> therefore I think it should be possible implicitly convert a delegate
>> returning a value, to a delegate returning void. The same for function
>> pointers as well. Example:
>>
>> void main ()
>> {
>>      int delegate () bar = { return 1; };
>>      void delegate () foo = bar;
>>
>>      int a = bar(); // here we call "bar" and handles the return value
>>      bar(); // here we call "bar" and ignores the return value
>>      foo(); // here we call "foo", same as the line above
>> }
>>
> I can see the appeal, but the abi makes it difficult.  As Walter said, what
> if the return value requires destruction by the caller?  What if the return
> is done through nrvo?  While they're called the same, the code generator
> handles them very differently.  If it works, it should work for all cases.
> Don't forget that you can trivially convert to a delegate returning void
> with the following syntax:
> void delegate () foo = { bar(); };

Why can't the compiler do something similar automatically. Then we won't 
have the problem if a lambda returns void or a value.

-- 
/Jacob Carlborg