Voldemort declarations inside structs with ctor initialization

[Idan Arye via Digitalmars-d]

On Tuesday, 27 May 2014 at 18:54:05 UTC, H. S. Teoh via 
Digitalmars-d wrote:
> Honestly, I don't see the need even for alpha-renaming -- I 
> can't
> imagine a use case where you'd want to do something like that. 
> I think
> straight up hashing of the function body is Good Enough(tm).
>
>
> T

Hashing the function body is not enough - you must also consider 
the closure!

     template Template(alias func){
         bool Template=func();
     }

     void foo(){
         int a;
         writeln(Template!(()=>is(typeof(a) : char))); //prints 
"false"
     }

     void bar(){
         char a;
         writeln(Template!(()=>is(typeof(a) : char))); //prints 
"true"
     }

If two delegates must have exactly the same scope, the usefulness 
of the hashing will be quite limited, but in many cases the same 
lambda can be declared in different scopes and still be the same. 
It all depends on how the lambda uses the closure - and checking 
this will be quite hard to implement...