[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.


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