#! perl -slw
use strict;
use Math::Random::MT qw[ rand ];
use Benchmark qw[ cmpthese ];

our $data = join '', map {
    sprintf '%-25s%15d', 'X' x int( rand 25 ) , int( rand 2**32 )
} 1 .. 125;

## extract 6 pairs at positions 3rd, 33rd, 50th, 75th, 100th 123rd
my $pair = 'A25 A15';
our $tmpl = "x[($pair)2] $pair x[($pair)29] $pair x[($pair)16] $pair"
          . "x[($pair)24] $pair x[($pair)24] $pair x[($pair)22] $pair ";

cmpthese -3, {
    regex => q[
        our $data;
        my @sixPair = ( 
            $data =~ m[(.{25})(.{15})]g 
        )[ 5, 6, 65, 66, 99, 100, 149, 150, 199, 200, 245,246 ];
    ],
    unpack=> q[
        our( $data, $tmpl );
        my @sixPair = unpack $tmpl, $data
    ],
};

cmpthese 1, {
    regex => q[
        our $data;
        my @sixPair = ( 
           $data =~ m[(.{25})(.{15})]g 
        )[ 4,5, 64,65, 98,99, 148,149, 198,199, 244,245 ];
        print 'regex  ', join '|', @sixPair;
    ],
    unpack=> q[
        our( $data, $tmpl );
        my @sixPair = unpack $tmpl, $data;
        print 'unpack ', join '|', @sixPair;
    ],
};

__END__
C:\test>junk4
          Rate  regex unpack
regex   3311/s     --   -91%
unpack 38783/s  1071%     --

regex  
XXXXXXXXXXXXXXXXXXXXXX   |      189677339|
XXXXXXX                  |      966124187|
XXXXXXXXXXX              |    -1269554066|
XXXXX                    |    -1916129141|
XXXXXXXXXXXXXXX          |     -479254076|
XXXXXXXXXXXXXXXXX        |      335028423

unpack 
XXXXXXXXXXXXXXXXXXXXXX|      189677339|
XXXXXXX|      966124187|
XXXXXXXXXXX|    -1269554066|
XXXXX|    -1916129141|
XXXXXXXXXXXXXXX|     -479254076|
XXXXXXXXXXXXXXXXX|      335028423