rval->ref const(T), implicit conversions

[tsbockman via Digitalmars-d]

On Tuesday, 19 January 2016 at 03:37:17 UTC, tsbockman wrote:
> It's ten times easier to write code that way, than the way Manu 
> complained about in the OP.

To clarify:

1) If `scope` were implemented, Manu's example would look like 
this:
     // Declaration
     void func(in CustomString s1, in CustomString s2);

     // Whenever rvalues need to be passed:
     func("hello", "world");

2) With my PR, it looks like this:
     // Declaration
     private void funcImpl(ref const(CustomString) s1, ref 
const(CustomString) s2);
     mixin acceptRVals!("func", funcImpl);

     // Whenever rvalues need to be passed:
     func("hello", "world");

3) Currently, we have this:
     // Declaration
     void func(ref const(CustomString) s1, ref const(CustomString) 
s2);

     // Whenever rvalues need to be passed;
     auto temp1 = "hello";
     auto temp2 = "world";
     func(temp1, temp2);

If A is the number of such functions, B is the number of `ref` 
arguments per function, and C is the number of calls where 
rvalues should be passed:

(2) Requires A more statements than (1).
(3) Requires B*C more statements than (1).

Obviously there is little reason to complain about any of this 
unless B >= 1 and C > A, so unless I'm missing something, my PR 
is a large improvement over the status quo.