Overzealous recursive template expansion protection?

[Gareth Charnock]

On 03/11/10 03:21, Robert Jacques wrote:
>
> struct BinaryOp(L,string op,R) {
>      pragma(msg,"Instansiating " ~ typeof(this).stringof);
>      BinaryOp!(typeof(this),s,R1) opBinary(string s,R1)(R1 r) {
>          pragma(msg,"Instansiating BinaryOp.opBinary ~L.stringof ~ op ~
> R1.stringof);
>          return typeof(return)();
>      }
> }
>
> struct Leaf {
>      BinaryOp!(typeof(this),s,R) opBinary(string s,R)(R r) {
>          pragma(msg,"Instansiating leaf.opBinary(" ~ R.stringof ~ ")");
>          return typeof(return)();
>      }
> };
>
> void main() {
>      Leaf v1,v2,v3;
>      pragma(msg,"");
>      pragma(msg,"======= This Compiles ======");
>      v1*(v2*v3);
>      pragma(msg,"");
>      pragma(msg,"======= This Doesn't ======");
>        (v1*v2)*v3;
> }
> Output:
> ======= This Compiles ======
> Instansiating BinaryOp!(Leaf,s,Leaf)
> Instansiating leaf.opBinary(Leaf)
> Instansiating BinaryOp!(Leaf,s,BinaryOp!(Leaf,s,Leaf))
> Instansiating leaf.opBinary(BinaryOp!(Leaf,s,Leaf))
>
> ======= This Doesn't ======
> Error: recursive template expansion for template argument
> BinaryOp!(Leaf,s,Leaf)

Thanks, the workaround seems to work. I've reported the bug:

http://d.puremagic.com/issues/show_bug.cgi?id=5160