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From: Andras Erdei (aerdei_at_[hidden])
Date: 20050310 02:51:12
On Mon, 7 Mar 2005 17:50:48 0700, Jonathan Turkanis
<technews_at_[hidden]> wrote:
> I can't tell what template parameters you think rational should have.
(it is because i don't know myself :O)
i think we need two parameters: one for specifying the precision,
and one for specifying the variant to use
the problems:
1. if we specify the precision as an integer, e.g. rational<1000> meaning a
rational with numerator range (1000,1000) and denominator range (1,1000),
then we restrict the possible underlying types to the integer type used as
the template parameter (and smaller)
a possible workaround is to specify the log of the limits instead, so e.g.
rational<31> would mean (2^31,2^31) and (1,2^31)  this is less flexible,
than the above one, but i can't come up with anything better
2. i don't know how can we implement the selection of UDTs: let's say
i have implemented a modular arithmetic bigint type, with up to a few
hundred bits of precision  how can i tell rational that it can select this
as the underlying type?
<snip>
> The above declaration was based on the assumption that multiple rounding
> policies should be supported. If there's only one way to round, then rounding
> can be merged into the checking policy.
i don't see how this depends on having more than one kind of rounding:
either you round, or you check, cannot do both at the same time  do i
miss something?
br,
andras
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