Re: [boost] Re: Fixed-Point Decimal, version 2

From: Beman Dawes (bdawes_at_[hidden])
Date: 2002-11-05 20:53:03

At 09:36 AM 11/5/2002, Bill Seymour wrote:

 >Mattias Flodin wrote:
 >>
 >> namespace detail {
 >>     struct round_down_tag {};
 >> 	struct round_up_tag {};
 >> }
 >> namespace {
 >>     const detail::round_down_tag round_down;
 >> 	const detail::round_up_tag round_up;
 >> }
 >>
 >> We can now make two separate overloads of operator[]
 >> that hold different return types:
 >>
 >> detail::round_down_proxy operator[](detail::round_down_tag);
 >> detail::round_up_proxy operator[](detail::round_up_tag);
 >>
 >
 >I wanted to make the rounding mode extensible so that we
 >could have user-defined rounding modes.  It seems like
 >we'd lose that if we needed an operator[]() member for
 >each rounding mode.

If I remember the original discussions correctly, it turns out that 
business applications use a variety of rounding rules. Because of legal and 
other pressures, they really have to use certain rules. Thus user-defined 
rules ensure accomodation.

Bill, please correct me if that isn't right.

--Beman