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Postings from July 2001
# This makes no sense. ?: tests a boolean value, which is either true or false.
# There is no ternary state for a boolean value. True/False, Yes/No, On/Off,
# 1/0. Are you suggesting Yes/No/Maybe? Or are you redefining True and False?
No. He's effectively saying this:
condition ? executed-if-positive : executed-if-zero : executed-if-negative
It doesn't quite fit into simple boolean logic. This has the potential to be useful for sorters:
@indices=sort { $ary[$a] <=> $ary[$b] ? -1 : 0 : 1 } @indices; #sort by values of another array in
reverse order
Yes, that last example can be done with a simple $ary[$b] <=> $ary[$a], but I'm trying to show you
what this feature does and I just woke up so my brain isn't up and running yet. :^)
# Doesn't matter. What you're asking has no counterpart in boolean logic, and
# as such would make no sense in any computer language. You may have an idea,
# but you are saying it wrong if you do.
There are plenty of things that have no counterpart in boolean logic. Where are loops defined in
Boolean logic?
--Brent Dax
brentdax1@earthlink.net
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