/boggle

Erm, why split to immediately rejoin with the same character? print $scroll->Contents(), "\n"; (not being familiar with Tk that may require a scalar after the print, but at any rate it should accomplish the same thing without the extra round trip).

OP: "Preferably (if it is possible) the text could be extracted as an array ..."

---

DWIM is Perl's answer to Gödel

Oop, quite right. I missed that part of the original question.

If the OP's trying to post-process the contents line-by-line before printing that's something completely different of course, but I didn't get that from the overall question (and it only would seem that way when you actually read that one un-parenthetical parenthetical aside which I missed).

Otherwise the objection still remains: if you're just trying to print the contents out somewhere, it's unnecessary work to split to lines just to add back newlines.

Update: And even if you are post-processing things from an array I'd tend to use something along the lines of for( @lines ) { my $line = munge($_); print $line, "\n"; } rather than joining for one big print just in the interest of efficiency.

Useless observation: Posting #2000. Break out the crepe paper and confetti.

Like Fletch asked, why separate the lines from the widget? I combined the code and ran it, and it worked fine without splitting the lines.

#!/usr/bin/perl -w 

use strict; 
use Tk; 
    
my $maincolor='red'; 

my $mw = MainWindow->new; 
$mw->minsize(qw(250 200)); #x y 
$mw->configure(-title=>'PROGRAM', -background=>$maincolor); 

my $frame_1=$mw->Frame(-borderwidth => 3, -background => $maincolor)->
+pack( -side=>'top', -fill=>'x'); 
$frame_1->Label(-text => 'Scroll', -background=>'yellow',)->pack(-side
+ =>'left'); 
    
my $scroll=$mw->Scrolled("Text", -scrollbars => 'e', -width => 10, -he
+ight => 10,)->pack; 

my $frame_2=$mw->Frame(-borderwidth => 3, -background => $maincolor)->
+pack( -side=>'top', -fill=>'x'); 
    
$frame_2->Button(
    -text => 'Print', -width=>7, -command=>\&doPrint
    )->pack(-side =>'bottom');
   
MainLoop;


sub doPrint {
    #my @lines = split /\n/, $scroll->Contents ();
    #print join "\n", @lines;
    my $lines = $scroll->Contents();
    print $lines;
}
[download]

jdtoronto

See the reply to Fletch.

BTW, why introduce a variable, or even the named sub come to that?

$frame_2->Button(
    -text => 'Print', -width=>7,
    -command=>sub {print $scroll->Contents ()},
    )->pack(-side =>'bottom');
[download]

does what is required without the sub or variable, but doesn't show OP how to get the lines into an array and doesn't illustrate the technique required to use a named sub for the command handler.

It may well be that OP doesn't require instruction in such things and possibly no-one who comes after will benefit, but it wasn't much effort to illustrate those techniques and someone may learn from it.

---

DWIM is Perl's answer to Gödel

The worry is that they might get the wrong idea from it: I need to print out these lines, so I'll split things into an array and then use join when I print because I saw that code on PerlMonks so it must be right.</cargocult>

I actually think your above answer is better because it does directly answer the question. You could always supplement it with asides about "to get an array of the lines use split like ...", or "if you're going to do complex processing before printing the contents you might want to use \&process_and_print and move the actual work to sub process_and_print { ... }".

But that's just me.