On Tue, Aug 30, 2011 at 10:23 PM, Mostafa <mostafa_working_away@yahoo.com>wrote:
Boost.Optional seems to really have a lot of potential for what I want to do, but one thing about it has been nagging me, specifically it's assignment semantics for wrapped references being different from the semantics of bare C++ references (see http://tinyurl.com/4yna643).
So...you don't agree with the rationale?
Has/have the author(s) of the library or anyone considered disallowing assignment for Boost.Optional types that wrap references, and if so, what would the consequences of this entail? I rather disallow assignment in this case, then have what's basically a wrapper class behave partially differently than the type it's supposed to emulate.
Given that there's an entire section of the documentation devoted to the semantics of assignment, I'd infer the author(s) consider the various possibilities for assignment, including disallowing it. If you disallowed assignment for optional<T&>, then surely you would likewise need to disallow default constructability, and then how would an optional<T&> really be any different from a T& other than the syntactic clutter? Perhaps you can elaborate on why the current assignment semantics are troubling to you...? - Jeff