Re: [Boost-users] type_erasure question

Subject: Re: [Boost-users] type_erasure question
From: Steven Watanabe (watanabesj_at_[hidden])
Date: 2013-04-07 14:22:17

AMDG

On 04/07/2013 08:40 AM, Aleksandar Fabijanic wrote:
> Looking at the type_erasure example:
> 
> typedef any<boost::mpl::vector<copy_constructible<>,
>         typeid_<>, addable<>>
>> any_type;
> 
> any_type x(1.1);
> any_type y(1);
> any_type z(x + y);
> 
> Apparently, without placeholders for x and y, this is undefined behavior.
> Am I interpreting it right? If so, shouldn't it fail to compile or at least
> throw an exception at runtime?
> 

It's impossible to make this fail to compile.
Undefined behavior does not mean throw an exception;
it means all bets are off.  If you add relaxed
to the concept, then you'll get an exception.

In Christ,
Steven Watanabe