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Subject: Re: [boost] Boost.mpl : change of sequence models not reflected in online docu
From: Steven Watanabe (watanabesj_at_[hidden])
Date: 2008-09-22 10:39:00


AMDG

Ingo.Loehken_at_[hidden] wrote:
> boost 1.35 (boost::mpl::vector)
>
> models a front extensible sequence. of course this does not make sense,
> because inserting at front implies n operations, where the docu states it
> takes only constant compile time.
>
> boost 1.36 (boost::mpl::vector)
>
> so an compile time assertion tells, that push_front is not supported for
> vectors.
> (docu dont states so)
>

push_front is supported for mpl::vector.

> boost 1.35 (boost::mpl::list )
>
> is a front and back extensible sequence, so push_front and push_back are
> supported as for std::list (that ok).
>
> boost 1.36 (boost::mpl::list)
>
> is no longer back extensible, because a compile time assertion tells, that
> the
> push_back is no longer supported for lists. maybe its planned to change
> the
> implementation to a recursive list, then inserting at back, will take
> O(n), but
> a list must support push_back. please fix that.
>
> docu states, a list is front and back extensible (inconsitent to
> assertion).
>

Where do the docs say that mpl::list is back extensible.
AFAIK, mpl::list has never supported push_back.

Could you please post specific code which fails that
you think ought to succeed?

In Christ,
Steven Watanabe


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