use strict;
use warnings;
use Benchmark qw(cmpthese);

my $str = <<STR;
just wondering how i can have perl display part of my long memo.  basically i
want the first lets say 255 charachters of the paragraph.  im really new to
perl so i don't know how i would come about this?...[ read more ]
STR

my $maxlen = 160;

cmpthese
    (
    -2,
        {
        'graff'  => \&graff,
        'graff2' => \&graff2,
        'duff'   => \&duff,
        'duff2'  => \&duff2,
        'jbrug'  => \&jbrug,
        'jbrug2' => \&jbrug2,
        }
    );
   
sub graff {
    my $txt = substr $str, 0, $maxlen;
}

sub graff2 {
    my $txt = substr $str, 0, rindex $str, " ", $maxlen;
}

sub duff {
    my $txt = $str;
    $txt =~ s/(.{1,$maxlen})\b.*/$1.../;
}

sub duff2 {
    my ($txt) = $str =~ m/(.{1,$maxlen}\b)/;
}

sub jbrug {
    my $txt = $str;
    $txt =~ m/.{$maxlen}/gs;
}

sub jbrug2 {
    my @a = split("",$str);
    my $txt = '';
   
    for (my $i=0; $i<$maxlen; $i++) {
        $txt .= $a[$i];
    }
}

##</code><code>##

            Rate  jbrug2    duff   duff2   jbrug  graff2   graff
jbrug2    1348/s      --    -99%    -99%   -100%   -100%   -100%
duff    101001/s   7393%      --    -59%    -73%    -94%    -95%
duff2   245077/s  18082%    143%      --    -35%    -84%    -89%
jbrug   379315/s  28041%    276%     55%      --    -76%    -82%
graff2 1556035/s 115341%   1441%    535%    310%      --    -28%
graff  2162638/s 160344%   2041%    782%    470%     39%      --