Re: [Boost-users] large variant performance compared (50 elements)

Subject: Re: [Boost-users] large variant performance compared (50 elements)
From: Steven Watanabe (watanabesj_at_[hidden])
Date: 2011-01-09 23:22:36

AMDG

On 1/9/2011 7:57 PM, Joel de Guzman wrote:
> On 1/10/2011 7:35 AM, Mathias Gaunard wrote:
>> On 09/01/2011 17:29, Steven Watanabe wrote:
>>> On 1/9/2011 6:03 AM, Mathias Gaunard wrote:
>>>> Writing a variant replacement is actually quite easy, and doing so
>>>> would greatly reduce your compile times.
>>>> Variant is old, full of quirks, and doesn't scale well. Why it even
>>>> requires its MPL input sequence to be Front Extensible (which it
>>>> doesn't even state in its documentation) is beyond me. This is a very
>>>> annoying limitation that makes it impractical to use with a large
>>>> amount of types, since compatibility with joint_view would be very
>>>> nice in that situation.
>
> Agreed. Perhaps it's time for V2 that does not necessarily have to be 
> fully
> backward compatible.

Why exactly would we need to break backwards
compatibility?  Eliminating the Front Extensible
requirement shouldn't break anything.  I don't
know of anything in the interface of variant that
would seriously interfere with a better implementation.
I know that assignment is a mess, but there's
a good reason it works the way it does.

In Christ,
Steven Watanabe