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From: David Abrahams (dave_at_[hidden])
Date: 2008-04-27 21:50:58


on Fri Mar 07 2008, Steven Watanabe <watanabesj-AT-gmail.com> wrote:

> AMDG
>
> Giovanni Piero Deretta wrote:
>> It seems a perfect application for fold:
>>
>> template<typename Seq>
>> struct or_seq
>> : mpl::apply<
>> mpl::fold<mpl::_1, mpl::false_, mpl::quote2<mpl::or_> >
>> , Seq
>> > {};
>>
>> template<typename Seq>
>> struct and_seq
>> : mpl::apply<
>> mpl::fold<mpl::_1, mpl::true_, mpl::quote2<mpl::and_> >
>> , Seq
>> > {};
>>
>
> Not quite, because we want it to short circuit.
> Not to mention that quote2 will not work on and_ and or_.

Yeah, these should be rewritten in terms of mpl::find.
Not sure why mpl::apply was used here either, though maybe I'm missign
something.

-- 
Dave Abrahams
Boost Consulting
http://boost-consulting.com

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