ADL

[Walter Bright via Digitalmars-d]

On 9/2/2016 5:15 AM, Manu via Digitalmars-d wrote:
> In C++, there is this ADL thing (argument dependent lookup).

Yeah, I know about Koening lookup. It was a hack added to C++ to make operator 
overloading work.


> D doesn't seem to have this,

That's right, and it's on purpose :-)


> and that is proving to be quite problematic. What's the work around?

Not a workaround, as D does not need ADL. This is how to do it:

extern (C++, bob) {
   struct S {}
   void f(S s);
}

extern (C++, joe) {
   struct T {}
   void f(T t);

   void test()
   {
     T t;
     f(t); // obviously works, T is in the local namespace

     alias f = bob.f;  // bring bob.s into current scope
     bob.S s;
     f(s);  // no problemo
   }
}


The 'alias' construct gives good control over which symbols are visible in which 
scopes.