Compile-time exceptions

[Denis Koroskin]

On Tue, 25 Nov 2008 15:28:53 +0300, bearophile <bearophile at lycos.com>  
wrote:

> Christopher Wright Wrote:
>> I don't know what this is doing. That code fragment won't compile, and
>> it isn't showing usage.
>
> Sorry:
>
> struct _add { T opCall(T.init + T.init)(T x) { return x+x; } }
> _add add;
>

Did you mean:

struct _add { typeof(A.init+B.init) opCall(A, B)(A a, B b) { return a + b;  
} }
_add add;

auto x = add(3, 0.1415926); ?

> Now you can give it to a function, without the need of specializing it  
> for a type T first (you can't give the pointer to a template). (This may  
> also be faster, because there isn't a delegate to call).
> (Haskell is statically typed and allows you do more complex things with  
> a clean enough syntax).
>

Yes, it is a nice trick.