On 06/16/12 21:22, bearophile wrote:
> Guillaume Chatelet:
>
> I like hard books, if they give something valuable back.
I think you'll find it rewarding.
> I see. is that semantically different from this (beside being shorter)?
>
> struct NoZero {
> int value;
> this(int x) { value = x; }
> alias value this;
> invariant() { assert(value != 0); }
> }
> void main() {
> auto a = NoZero(5);
> auto b = NoZero(0);
> }
That's a good one ! I forgot about the _invariant_ keyword.
It's pretty close. For what I understood of x10 (I'm not using it yet
just interested in the language) the compiler will also enforce the
invariance at compile time not solely at runtime. ie
void main(){
NoZero a = 0; // shouldn't compile
}
Thx for the design though, I keep it in my toolbox.
--
Guillaume
