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From: Andy Little (andy_at_[hidden])
Date: 2005-02-28 06:51:23

Hi All,

     What is the current status of compile time fractions / rationals?

    Various directions are

   1 Alexei Gurovois in boost/mpl/math/rational_c.hpp

    2 Cromwell Enages work on the files section

   3 Hugo Duncans:
    However the three are not compatible with each other

    In Cromwells (named fraction_c) and Hugo Duncans the numerator and
denominator are mpl Integral Constants not values, as in Alexeis original.

                    mpl::rational_c<int,1,2>::denominator; // == 2
                    mpl::rational_c<int,1,2>::denominator::value; == 2

    Cromwell's version is not a nullary_metafunction whereas Hugo Duncans
and Alexeis are. This is the right thing IMO because the type can be reduced
    eg 2/2 ---> 1,
Also see

I appreciate that there my be advantages to Cromwells and Hugo Duncans
versions.. Ultimately either the version in the release should be removed/
modified or 'lived with'.

Anyone have any thoughts. And is anyone still working on this?

Andy Little

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