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From: Robert Ramey (ramey_at_[hidden])
Date: 20050202 15:48:06
At first I didn't understand this. But upon a little reflection I think it
is a very interesting idea. If Dimensional analysis were built on top of
this, odd ball cases such as "nanovolts per sqrt(Hz)" could be handled as
specializations of <T,X1> op <T,X2> while default dimensional analysis would
be used it implement the default cases.
Robert Ramey
Matt Austern wrote:
> There's actually something even lower level than a dimension library.
> In essence, what we've got is:
>  We're generalizing the notion of an arithmetic type T to a type of
> the form <T,X>, where X is some sort of tag.
>  For any X1 and X2 and any arithmetic operation 'op', we have rules
> for whether <T,X1> op <T,X2> is well defined. If it is then the
> result is tagged as <T,X3>, and we have rules to determine X3 in terms
> of X1, X2, and op.
>
> All of the knowledge about how to represent dimensional systems (mpl
> vectors, compiletime fractions, etc.) is higher level than this.
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