RFC: scope and borrowing

[deadalnix via Digitalmars-d]

On Sunday, 21 September 2014 at 15:10:23 UTC, Andrei Alexandrescu 
wrote:
> Is this because of problems with ref's definition, or a natural 
> consequence of supporting ref parameters? -- Andrei

There is various reason why this is complex:
  - classes must often be handled specifically.
  - auto ref is not very controllable and tend to end up with an 
combinatorial explosion of special cases.
  - it is complex to find out if something is ref or not in 
generic code.
  - it is not possible to conditionally declare something as ref. 
It is true of other qualifiers, but ref change the semantic in a 
more deeper way than, say, dropping pure or @safe.
  - you may want to use ref for very different semantics, which 
lead to different policies about what should be ref or not. There 
is no other way to implement these policies than spaghetti static 
if with meatball code duplication.