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SubjectRe: [IDEA+RFC] Possible solution for min()/max() war
Date
Graham Murray <graham@barnowl.demon.co.uk> writes:

> Daniel Phillips <phillips@bonn-fries.net> writes:
>
> > More than anything, it shows that education is needed, not macro patch-ups.
> > We have exactly the same issues with < and >, should we introduce
> > three-argument macros to replace them?
>
> Would it not have been much more "obvious" if the rules for
> unsigned/signed integer comparisons (irrespective of the widths
> involved) were
>
> 1) If the signed element is negative then it is always less than the
> unsigned element.
>
> 2) If the unsigned element is greater than then maximum positive value
> expressible by the signed one then it is always greater.
>
> 3) Only if both values are positive and within the range of the
> smaller element are the actual values compared.

With infinite-precision arithmetic, yes; of course min() should just
return the smaller value.

But what would the C type of "min" be for comparing, say, signed and
unsigned longs? The range of possible results does not fit in any
integral type. (Repeat the question for signed/unsigned "long long"
if "long long" is your answer.)

- Pat
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