On Mon, Nov 29, 2004 at 10:15:52AM +1100, Michael Kraus wrote:
> Which is better to use, a for/foreach loop or map function when doing
> some basic comparisons and assignments?
>
> E.g.
>
> for my $datum (keys %{$rh_vars}) {
> $max_length = length($datum) if length($datum) > $max_length;
> }
>
> OR
>
> map { $max_length = ($max_length > length($_) ? $max_length : length($_)
> } keys %$rh_vars;
>
> OR
>
> map { $max_length = length($_) if $length($_) > $max_length } keys
> %$rh_vars;
>
>
> Thanks heaps - some discussion on these basics would be great. My guess
> is that it would be the last one as it doesn't assign $max_length a
> value unless it has to.
Better is subjective here, especially as you don't say better for what,
but I would agree that x = y if z would be preferable to x = z ? y : x.
I would also suggest that using for instead of map in a void context is
better style, even though you won't take the hit of creating a list to
throw away that you used to, provided you are using a sufficiently
recent perl. (By the way, perl-5-8-6 has just been released.)
So, of your alternatives, I would use the first. But I would prefer to
use:
use List::Util "max";
my $max_length = max map length, keys %$rh_vars;
--
Paul Johnson - [EMAIL PROTECTED]
http://www.pjcj.net
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