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Re: straw-man [was Re: arithmetic issues]

This page is part of the web mail archives of SRFI 77 from before July 7th, 2015. The new archives for SRFI 77 contain all messages, not just those from before July 7th, 2015.



> From: bear <bear@xxxxxxxxx>
>> On Fri, 20 Jan 2006, William D Clinger wrote:
>> Secondly, the standardization of the fixnum/flonum base
>> will improve the portability of programs that, for whatever
>> reason, already use implementation-specific fixnum or flonum
>> operations.
> 
> Erf....  Aesthetics aside, yes, it *is* correct, if you're
> going to have these modular-ring fx-foo and limited-precision
> fl-foo operations, to make them different from general numeric
> operations.  This is because they are different operations
> from the general numeric operations, and in some circumstances
> give different answers.
> ...

- Upon more reflection, given that it's likely unreasonable to presume
  that an <exact> implementation must (or even could) reliably support
  infinitely precise calculations/representations, it must then support
  finite precision calculations, thereby necessitating its definition
  of overflow semantics, basically leaving the choice of either modular
  or saturating semantics; where either may be considered reasonable,
  it seems undisputed that modular semantics tend to be the simplest
  and most natural default of most machine and/or SW implementations,
  and does not preclude the throwing of a recoverable overflow exception
  if supported by the base implementation.

  (although believe exposing explicitly typed functions are unnecessary)