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in reply to Display shortened paragraph

TIMTOWTDI
update: More or less the same idea as duff i see :) 
#!/usr/bin/perl -w

use strict;
my $txt = "just wondering how i can have perl display part of my long 
+memo. basically i want the first lets say 255 charachters of the para
+graph. im really new to perl so i don't know how i would come about t
+his? a regex perhaps? just started reading about that today. so basic
+ally something like";
my $n = 20;
$txt =~ m/(.{$n})/gs;
print $1;

[download]


ok, yet another way then :) 
#!/usr/bin/perl -w

use strict;

my $txt = "just wondering how i can have perl display part of my long 
+memo. basically i want the first lets say 255 charachters of the para
+graph. im really new to perl so i don't know how i would come about t
+his? a regex perhaps? just started reading about that today. so basic
+ally something like";

my @a = split("",$txt); 

for (my $i=0; $i<20; $i++) {
    print $a[$i];
}

[download]


"We all agree on the necessity of compromise. We just can't agree on when it's necessary to compromise." - Larry Wall.

Replies are listed 'Best First'.
Re^2: Display shortened paragraph
by Anonymous Monk on Feb 01, 2006 at 06:09 UTC
    hi! works, but how would i shorten the paragraph so that it does not cut off a word if it reaches the max char. limit? for example..."just wondering how..." compared to "just wonder h..." ---notice how it cuts off the "ow" in "how"....thanks
[reply]
      Since people have shown how the use of a regex approach tends to be slower, here's a way to observe word boundaries (well, spaces between words, anyway) without using a regex: 
      my $maxlen = 20;
my $longtext = "This is some very long string that needs to be truncat
+ed to $maxlen characters...";

my $trunctext = substr( $longtext, 0, rindex( $longtext, " ", $maxlen 
+));

print "$longtext\n$trunctext\n";

      [download]
      The rindex function, like substr, is faster than a regex match.
[reply]
[d/l]
      By using duff's solution with the Matching the word boundary \b so that you don't chop off the text in the middle of a word.

      update:
      A clumsy other way to do this :) 
      use strict;
use warnings;

my $txt = "just wondering how i can have perl display part of my long 
+memo. basically i want the first lets say 255 charachters of the para
+graph. im really new to perl so i don't know how i would come about t
+his? a regex perhaps? just started reading about that today. so basic
+ally something like";

my @a = split("",$txt); 
my $l = 7;

for (my $i=0; $i < $l; $i++) {
    print $a[$i];
    $l++ if ($i ==($l-1) && ($a[$i] ne " " )) ;
}

      [download]


      "We all agree on the necessity of compromise. We just can't agree on when it's necessary to compromise." - Larry Wall.
[reply]
[d/l]
      A reply falls below the community's threshold of quality. You may see it by logging in.
      actually the code given by graff works just fine:

      my $max = 230;
(my $copy = $string) =~ s/(.{1,$max})\b.*/$1.../;
print "$copy\n";

      [download]
      Thanks!
[reply]
[d/l]

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