Fernando Cacciola wrote:
So my current proposal would be:
Remove direct-assignment. Let copy-assigment be the only way to define the wrapped value Add make_optional() and make_optional_ref() as shorcuts to help with copy-assignment Keep none-assignment as the only wat to clear the wrapped value.
Does this mean that construction from T is also suggested to be removed? I assume not... Anyway, If I'm required to write optional<T> o = x; ... o = optional<T>(y); or optional<T> o = x; ... o = make_optional(y); then it should be considered that this generates an additional temporary instance of y (of type T). Direct assignment from T doesn't suffer from this. Working around this makes me write optional<T>(y).swap(o); or make_optional(y).swap(o); which is completely different...