Re: [boost] Fixed-Point Decimal Type

From: Gabriel Dos Reis (Gabriel.Dos-Reis_at_[hidden])
Date: 2001-05-15 14:33:54

Beman Dawes <bdawes_at_[hidden]> writes:

| So a question is do you support that by having a whole bunch of different 
| functions, or by the class template taking some kind of a parameter 
| (perhaps a traits or policy class) performing the rounding desired?

I'm leaning toward a trait-based solution.

That would certainly satisfy the LIA-1 requirement

   A method shall be provided for a program to obtain the value of the
   derived constant /rnd_style/ for each floating point data type
   provided. 

| If different rounding rules are never mixed for a given fixed-point object, 

The mixing of different rounding rules could be handled by providing
conversion functions from one type to another using the appropriate
rounding function.

| it might be a lot cleaner to have one template parameter (which could 
| default to a useful rule) that having a huge number of very ugly, basically 
| duplicate, functions:
| 
|  >    mul_with_truncate(a,b)
|  >    mul_with_rhlsd_up(a,b)
|  >    mul_with_rhlsd_ran(a,b)
|  >    mul_with_noround(a,b)
| 
| and then it later turning out that there was yet another rounding rule 
| needed.

100% agreed.

-- Gaby