Re: [boost] units review

From: Noah Roberts (roberts.noah_at_[hidden])
Date: 2007-03-29 18:50:31

Steven Watanabe wrote:
> AMDG
> 
> Matthias Schabel <boost <at> schabel-family.org> writes:
> 
>>> Since that time I have made a few changes which make it
>>> trivial to switch to mpl::plus etc.  I agree that that
>>> would be a good thing.
>> It would be good, but, ultimately, this is an implementation detail  
>> that should have no impact on the library's end users...probably not  
>> something that needs to be a top priority...
> 
> Aren't users allowed to manipulate dimension lists
> directly?

Exactly.  One would expect it to follow conventions.  Also see the 
static_rational, which I think needs its own review and be added to the 
math library.
> 
>> I would rather not make the code totally incomprehensible unless  
>> there is a very clear and compelling reason to. It takes less than 30  
>> seconds for me to recompile all 22 example programs on my machine,  
>> which is quite acceptable...
> 
> Exactly my conclusion.

I did not time it but I did compare it relative to both my own home 
brewed quantity class and to doubles.  Our software can take a long time 
to compile already and this particular implementation was at least 10x 
as slow to compile as doubles.  This could have significant impact on 
its utility as well; it might be entirely impractical to use in very 
large projects that do a lot of computations.