Andy Little wrote:
I am aware that Walter Browns original SI units could be used with various unit systems and units could even be converted between them, but in PQS I have (rightly or wrongly ) opted to only cover SI units to limit the scope of the project to something manageable. I realise that this is disappointing however there are enough problems within one system ( such as the problem of linear algebra on quantities discussed in another thread), that I would prefer to solve them satisfactorily for one system rather than try to create a half-finished solution to cover every system.
There's a big difference between providing flexibility in the design and actually using that flexibility to implement everything. I would be perfectly happy with a library that provided flexibility for other units (decoupling prefixes, allowing non-power-of-10 prefixes, etc.) but only actually implemented SI units. Just as t2_quantity and t3_quantity can come later, so can other units systems.
I should however try to ensure that the library can potentially be extended to other unit systems as far as possible, and currently it is weak in that area.
I would like that very much. I'm willing to help in whatever way possible. Would it help to gather a list of flexibility requirements? The Boost Wiki would be a good place for that.
OK. I am ware that the whole rigmarole involved in defining types and units could be improved. Composition with Boost Typeof would help as well as improved Concept docs perhaps.
I actually didn't find this too intimidating, but then I've done a fair amount of TMP. Of course, if it can be improved, all the better! -Dave