Re: [boost] Stream input and output of NaN and infinity

From: Robert Ramey (ramey_at_[hidden])
Date: 2006-05-16 10:44:35

Geoffrey Irving wrote:
> On Mon, May 15, 2006 at 11:18:08PM -0700, Robert Ramey wrote:
>> Jeff Garland wrote:
>>
>> <snip
>>
>>>> A program which produces an undefined result is "broke"
>>>
>>> I guess all of 'math' is broken then too?  The only way to deal with
>>> singularities in math is to effectively 'bail-out' -- say, well
>>> don't do that.
>>
>> That's how math works - I think C++ should work the same way.
>
> Sorry for the short rant:

No apologies necesssary - that's what we do here.

>
> Saying that 1/0 means bail out is "how math works" is missing the
> point.
> The real number line, plus infinities, plus NaN, is one of the
> simplest extensions of the real numbers which is closed under the
> basic arithmetic operators.  The idea of adding positive and negative
> infinities to the
> real line is hundreds of years old.  Arguing that 1/0 should crash
> because that's what happens in "math" is the same as arguing that
> 2*max_int should crash because that's what happens in math...unless
> you have modulo arithmetic.

True - I would argue that as well

> As for the original topic, I very much like the proposal to have +-inf
> and NaN as the only special values.
>
> Geoffrey
> _______________________________________________
> Unsubscribe & other changes:
> http://lists.boost.org/mailman/listinfo.cgi/boost