Compile time function execution...

[Andrei Alexandrescu (See Website For Email)]

Walter Bright wrote:
> Michiel wrote:
>> That's a great feature! A couple of questions, if I may:
>>
>> * Can sqrt still call another function?
> 
> Yes, as long as that function can also be compile time executed. 
> Recursion works, too.
> 
>> * Does it still work if classes or structs are involved in any way? What
>> about enums? What about arrays?
> 
> No, yes, array literals only.
> 
>> * Why is the second sqrt(10) run at runtime?
> 
> Because the compiler cannot tell if it is a reasonable thing to try and 
> execute it at compile time. To force it to happen at compile time:
> 
> template eval(A...) { alias A eval; }
> 
> writefln("%s", eval!(sqrt(10)));
> 
> which works because templates can only take constants as value arguments.

The feature of binding expressions to aliases will break eval.

Andrei