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



> 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)