I was thinking of RFC'ing tri-state logic. Would it be worthwhile to
make it seperate or to extend your RFC?

I'd like to be able to mimic what the rules for nulls are in databases.
(I only know sybase's rules, so there may be differences between vendors.
Could somone that is aware of the ANSI standard chime in.)

        number + NULL = NULL
        number * NULL = NULL
        number - NULL = NULL
        number / NULL = NULL

        string + NULL = string

        value == NULL : false
        NULL == NULL : false
        value != NULL : false
        NULL != NULL : false


In sybase, summing or averaging a column with nulls simply ignores the
nulls. How this would effect the proposed reduce function or perhaps
that map/grep functions I don't have a clear proposal.

(I also found an interesting effect in Sybase

        NaN != NaN      false
and     NaN == NaN      false
)

<chaim>

>>>>> "PRL" == Perl6 RFC Librarian <[EMAIL PROTECTED]> writes:

PRL> The handling of various abnormal numeric entities like infinities
PRL> (positive, negative), not-a-numbers (NaNs, various kinds of those,
PRL> signaling, non-signaling), epsilons (positive and negative) is left to
PRL> the native math libraries.  A more concerted effort to standardise the
PRL> behaviour of Perl across the platforms would be desirable.

-- 
Chaim Frenkel                                        Nonlinear Knowledge, Inc.
[EMAIL PROTECTED]                                               +1-718-236-0183

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