[boost] Re: Yet another physical quantities unit library (0.1) uploadedtoyahoo groups files section

From: Andy Little (andy_at_[hidden])
Date: 2004-01-16 16:46:27

"Phil Richards" <news_at_[hidden]> wrote

> For better or worse, warts and all, I've uploaded my working prototype.
> It isn't meant to be complete, and it certainly in anything like a final
> form, but it sort of does some of the right things.
>
> The zip-file is under boost yahoo groups with name yapqul-0.1.zip
> It has only been tested with g++ 3.3.2.
[snip]

> Have a laugh, rip it apart.  All feedback welcomed, not matter how
> unwelcome it is...

Hi,
Have tested yapqul on VC7.1 . (aside "pqs-script.cpp" Needs VC7.1 language
setting set to "force conformance in for loops" BTW...which is correct but
not always default)

Basically I like the syntax (naturally ;-) ) , and for SIUnits-syntax fans
that syntax is catered for too. This is good because at one level (user
interface) there has been a lot of disagreement. Based on that I hope to
provide a Yanl style demo too..

Overall comparing the three pqs, Yanl and yapqul... and looking at scope for
convergence/conversions. I think there is good reason for optimism. In the
next version of pqs I shall:
1) use the Rational (static_rational) type (like the rational powers demo
BTW).
2)Include a units param.(rather than bits and pieces).
 I personally like the implicit conversion syntax, so I plan to make this a
configurable trait if possible. Also noted the convert_units<T>(s) in
action, which feels nice. ( and angles etc)
3) I hope also to provide some user configurable conversions at the
value_type layer(using Fernando Cacciolas converter), hence the param will
be Value_type_traits or something like it. (No idea how any of this will
work yet.)

So at the higher level the three libs should start to look relatively
similar.(Your params order is probably better than the one in my pqs Concept
Check post.) On that issue... could take a look at pqs-1-00-01 dimensional
analysis error handling, which uses (basic) concept checking to help
distinguish these type of errors.

There are still a lot of parts that I havent looked at yet, but (possibly
because it is meant for a similar area of work to mine)... basically I like
it :-) There are some parts that I think I wont agree with( boost archives
for more:-) )... but the basic test is if I had found the lib on boost, I
would probably have quietly downloaded and been on my merry way.

regards
Andy Little.