On Mon, Dec 14, 2015 at 1:12 PM, Agustín K-ballo Bergé < kaballo86@hotmail.com> wrote:
On 12/14/2015 5:53 PM, Emil Dotchevski wrote:
On Mon, Dec 14, 2015 at 4:46 AM, Agustín K-ballo Bergé <
if the compiler says there is an error here because `normalized` needs a
default constructor, I'm gonna start suspecting something wrong is going on with the library. This is what I would naively expect `normalized` to be doing:
template <typename Vec> Vec normalized(Vec v) { return v /= length(v); }
It can't be implemented that way because the type of the argument might not be copyable.
Does this mean that the library explicitly supports movable-only types? That's somewhat unexpected, given that the library requires all type information necessary for embedded storage, but it's not a bad thing. It would be good to add this information to the reference documentation.
QVM is neutral wrt move semantics but views are non-copyable and non-movable because copy or move semantics would require a temporary object, which QVM views are carefully designed to avoid. You can assign to a view and it will convert to any compatible type, but you can't copy or move it. That's why you can chain views up with no overhead: any operation on a view or multiple chained views works with the original object, no other objects are created. Emil