Good idea, and we can even cover that one ourselves, too: 

sub is_ordered_according_to {
    my ($binary_predicate, @values) = @_;
    if (@values < 3) {
        return $binary_predicate->(@values);
    } else {
        return $binary_predicate->($values[0], $values[1])
            && is_ordered_according_to($binary_predicate, 
                                       @values[1..$#values]);
    }
}

sub less_than {
    return shift() < shift();
}

print is_ordered_according_to(\&less_than, 
1, 2, 3, 4, 5, 6) ? "yes" : "no", "\n" ;
print is_ordered_according_to(\&less_than, 
3, 2, 1, 4, 5, 6) ? "yes" : "no", "\n" ;
print is_ordered_according_to(\&less_than, 
1, 2, 3, 4, 6, 5) ? "yes" : "no", "\n" ;

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Christian Lemburg
Brainbench MVP for Perl
http://www.brainbench.com

In reply to Re: Re^3: Why not support this syntax? by clemburg
in thread Why not support this syntax? by MeowChow

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