On Mon, Mar 26, 2001 at 05:29:24PM -0500, John Porter wrote:
> Jarkko Hietaniemi wrote:
> > ST (or GR) applies to any situation where you your sort
> > comparator function isn't directly expressible with (Perl) primitives,
> > and worthwhile it is (like Yoda feel I) when the cost of converting
> > the keys (so that the primitives can again be employed) begins to
> > dominate the overall cost of sort().
>
> Of course. So how is the ST justified when you simply want to
> sort by length? I.e., why is this not sufficient:
Those of the School of Maniacal Optimization may prefer calling
length() only O(N) times, instead of O(N log N) times. Yeah, a weak
argument, but then again, I didn't claim length() as such being the
prime user of ST. I just jumped at your "fields" description, which
sounded odd to me. There need not be "fields" by any stretch of the
term. It's all about reduction to primitive-comparable and the
relative cost of it.
> sort { length($a) <=> length($b) } # I see no ST here.
>
> And this was alleged to be the most common case for ST.
--
$jhi++; # http://www.iki.fi/jhi/
# There is this special biologist word we use for 'stable'.
# It is 'dead'. -- Jack Cohen
