Re: [boost] Formal review or Variant Library (Ed B.)

From: Peter Dimov (pdimov_at_[hidden])
Date: 2003-02-19 10:20:40

David Abrahams wrote:
> "Peter Dimov" <pdimov_at_[hidden]> writes:
> 
>> It may be possible to use optional<T&> (is it supported?) or
>> optional< reference_wrapper<T> > but this looks like an "obfuscated
>> C++" entry to me compared to T*.
> 
> Good point.
> 
>> What's wrong with it? What does optional<T&> add?
> 
> Suppose you have a
> 
>      variant<mpl::list<int&, std::string&> >
> 
> How do you check to see if it contains an int&?

You don't. "int&" doesn't meet the variant requirements. Even if it did:

variant< int, int& > v;

How do you check to see if it contains an int&?