[Python-Dev] Re: Decimal data type issues

Kevin Jacobs jacobs at theopalgroup.com
Fri Apr 16 10:32:47 EDT 2004


Batista, Facundo wrote:

>[Casey Duncan]
>
>#- I find boolean arguments a general anti-pattern, especially given we
>#- have class methods. Why not use an alternate constructor like::
>#- 
>#-   pi = 
>#- Decimal.rounded_to_context("3.1415926535897932384626433832795")
>
>This is a good idea to me.
>
>We all must decide which of the following is better:
>
>  a) Decimal(number)     # no context used
>     Decimal(number, context)
>
>  b) Decimal(number)     # no context used
>     Decimal.using_context(number, context)
>
>"number" can be string, int, etc., but NOT float. The issue with rounding at
>a defined position has nothing to do with context.
>  
>

Don't forget that many financial applications use fixed scale and 
precision as
their primary mechanism for specifying Decimal types.  As such, it
would be very nice to have a constructor that took a literal representation
as well as scale and precision.  While using context is sufficient, it will
be unintuitive and may present an undue burden on many users.

So-many-people-to-make-happy-ly,
-Kevin




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