Re: DIP 1016--ref T accepts r-values--Formal Assessment

[Daniel N via Digitalmars-d-announce]

On Saturday, 9 February 2019 at 01:31:05 UTC, H. S. Teoh wrote:

Using lowering to lambdas as a way of defining semantics is not 
the same thing as actually using lambdas to implement a feature 
in the compiler!

While it can be convenient to do the latter as a first stab, 
I'd expect that the optimizer could make use of special 
knowledge available in the compiler to implement this more 
efficiently. Since the compiler will always use a fixed pattern 
for the lowering, the backend could detect this pattern and 
optimize accordingly.  Or the compiler implementation could 
lower it directly to something more efficient in the first 
place.


T

The lambda even correctly handles "@disable this(this);", I like 
it!

struct One { @disable this(this); }
void fun(ref One one) { }

One gun() { return One.init; }

void main()
{
  One one; one.fun();
  (One __temp0){ return fun( __temp0 ); }(gun()); // OK
}