For ultimate speed, use the magic split regex ' '. Say what? 

my $number = ( split ' ', $string, 3 )[1];

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Saves another 1% to 10% or so and it's even easier to type, though a little harder to remember:)

From perlfunc:split

As a special case, specifying a PATTERN of space (' ') will split on white space just as split with no arguments does. Thus, split(' ') can be used to emulate awk's default behavior, whereas split(/ /) will give you as many null initial fields as there are leading spaces. A split on /\s+/ is like a split(' ') except that any leading whitespace produces a null first field. A split with no arguments really does a split(' ', $_) internally.

The very fact that there is a special case made for the splitting of whitespace delimited fields suggests that someone felt that this was worthwhile optimising. Who knows, maybe that someone was even LW himself. 

#! perl -slw
use strict;
use Benchmark qw[ cmpthese ];

our $string = "zero   one  two three";

our $string = "zero   one  two three";
cmpthese( -5, {
    'list\s+'     => q[ my $num = ( split /\s+/, $string    )  [1] ],
    'anon\s+'     => q[ my $num = [ split /\s+/, $string    ]->[1] ],
    'list\s+3'    => q[ my $num = ( split /\s+/, $string, 3 )  [1] ],
    'anon\s+3'    => q[ my $num = [ split /\s+/, $string, 3 ]->[1] ],
    "list' '"     => q[ my $num = ( split ' ',   $string,   )  [1] ],
    "list' '3"    => q[ my $num = ( split ' ',   $string, 3 )  [1] ],
});
__END__
P:\test>test
            Rate  anon\s+ anon\s+3  list' '  list\s+ list\s+3 list' '3
anon\s+  13679/s       --     -13%     -47%     -48%     -56%     -57%
anon\s+3 15789/s      15%       --     -39%     -40%     -50%     -50%
list' '  25818/s      89%      64%       --      -2%     -18%     -18%
list\s+  26330/s      92%      67%       2%       --     -16%     -16%
list\s+3 31370/s     129%      99%      22%      19%       --      -0%
list' '3 31493/s     130%      99%      22%      20%       0%       --

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Examine what is said, not who speaks.
"Efficiency is intelligent laziness." -David Dunham
"When I'm working on a problem, I never think about beauty. I think only how to solve the problem. But when I have finished, if the solution is not beautiful, I know it is wrong." -Richard Buckminster Fuller
If I understand your problem, I can solve it! Of course, the same can be said for you.

In reply to Re: Re: coding style suggestion by BrowserUk
in thread coding style suggestion: (...)[1] vs. [...]->[1] by thens

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