On Wednesday, 26 December 2012 at 22:52:29 UTC, Jonathan M Davis
wrote:
On Wednesday, December 26, 2012 23:02:25 deadalnix wrote:
Sound like the wayt o go for me. But is ato ref needed in such
case ? Why not simply allow ref to behave that way ?
Because there's a very large difference between a function
intended to take
arguments by ref and one where you don't care. For instance,
what if popFrontN
suddenly accepted rvalues? Using it with rvalues would do
nothing. We had
problems with std.conv.parse precisely because there was a
compiler bug that
allowed you to pass string literals to it in spite of the fact
that it takes
its argument by ref and needs to mutate its argument.
That is a const bug not a ref bug.
With auto ref, you're specifically saying that you don't care
whether the
function is given an lvalue or rvalue. You just want it to
avoid unnecessary
copies. That's very different. And auto ref then not only then
protects you
from cases of passing an rvalue to a function when it needs an
lvalue, but it
makes it clear in the function signature which is expected.
- Jonathan M Davis
I suspect making the distinction is complicating uselessly the
language for a benefit that isn't really clear.
