Simon Buchan wrote:
Fernando Cacciola wrote:
Reece Dunn wrote:
Fernando Cacciola wrote:
Sam Partington wrote:
[...]
Why not use partial specialization so that optional< T > has the semantic sugar, but optional< T & > does not? Or is this already the case?
I'm not too fond of template classes that support different interfaces according to the properties of the template parameters. That just doesn't play along with generic programming where the type you optionalize can or cannot be a reference. Think of vector<bool> for instance. I rather keep looking for a consistent solution.
The difference being that vector<bool> has semantic (but not syntactic) differences, while optional<T&> would have syntactic (but not semantic) differences.
Right.. though I'm still reluctant to give references a special syntax.
And
template <class T> optional<T> foo(optional<T> ot) { ... ot = optional<T>(someTexpr); ... }
would always work.
That's why I suggest discarding direct assigment. Is only syntatic sugar.
Personally, though, I think dropping optional<T&> would be perfectly acceptable.
Somewhat acceptable, yes, but I'm still trying to save it. -- Fernando Cacciola SciSoft http://fcacciola.50webs.com/