Re: [Boost-users] library accumulator, example sum_accumulator

From: Eric Niebler (eric_at_[hidden])
Date: 2008-09-01 17:23:53

Kim Kuen Tang wrote:
> Hi all,
> 
> i ' ve written a piece of code to get the class sum_accumulator working 
> which is described in the user's guide
> http://boost-sandbox.sourceforge.net/libs/accumulators/doc/html/accumulators/user_s_guide.html#accumulators.user_s_guide.the_accumulators_framework.extending_the_accumulators_framework. 
> 
> 
> The function result must be provided with a struct dont_care.
> And the constructor of dont_care must be provided with a value to get an 
> instanciation.
> In my opinion a default constructor taking no arguments  for the struct 
> dont_care must exists so the user can write code like dont_care().
> 
> To get the example working i must write code like
> sumacc.result(*dont_care(0.0)*) to get the result from my accumulator.
> And this is a little bit unnecessary.
<snip>

The interface you're describing is an internal interface, consumed by 
the accumulator_set<>. End-user code should never be directly calling 
the result() member function of an accumulator implementation. 
Accumulators are not supposed to be used stand-alone ... only as part of 
an accumulator_set<>.

HTH,

-- 
Eric Niebler
BoostPro Computing
http://www.boostpro.com