From: Maarten Kronenburg (M.Kronenburg_at_[hidden])
Date: 2006-05-26 14:15:21
"The question "can it have two" is useful in many
cases where there is doubt."
I hope you agree that an unsigned integer
can never have two integers.
"Martin Bonner" <martin.bonner_at_[hidden]> wrote in message
> From: Maarten Kronenburg
> > To my knowledge
> (Aside: I think you mean by that "I am not aware of any evidence to
> contradict the suggestion that ...". If that is what you mean, "As far
> as I know ..." would be more idiomatic. Particularly as there is an
> English idiom "To my *certain* knowledge" which means "I know with
> absolute certainty that ...". N.B. Your English is already a whole
> heap better than my Dutch!)
> > the base type int does not
> > have a +0 and a -0.
> > So therefore I see no reason to specify this.
> C++ can be implemented on a sign and magnitude machine (I believe there
> are still some around). On such a machine an int can be either +0 and
> -0. (However I'm pretty sure the standard requires that those two
> values compare equal)
> > Derivation is a part of C++, so in my opinion
> > users must be able to derive from class integer
> > to make an integer with special properties.
> I think that would be a mistake.
> > How would you explain to a user that whatever
> > he/she does with integer, derivation is not an option,
> > because the destructor does not happen to be virtual.
> > This is what it boils down to in the end.
> They should use containment.
> > Once again I argue that an unsigned integer is an integer,
> > and a modular integer is an integer.
> > An unsigned int is actually a modular int with modulus 2^32.
> Actually the modulus is not specified. It cannot be smaller than 2^32,
> but it could be larger.
> Martin Bonner
> Pi Technology, Milton Hall, Ely Road, Milton, Cambridge, CB4 6WZ,
> ENGLAND Tel: +44 (0)1223 203894
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