There's a lot of repitition there as you can doubtless see. This suggests a loop. Here's an outline:

#!/usr/bin/env perl 
use strict;
use warnings;

my @things = qw/firefox chrome exploder/;
while (my $this = shift @things) {
        for my $that (@things) {
                print "Now compare $this with $that\n";
        }
        last if $#things < 1;
}
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You can obviously replace the print statement with whatever block you require for each permutation of entries in @things. HTH.

Thanks. I will try to find a better solution. And yes , i can doubtless see it..obviously. And what does it mean HTH ?
Lost in translation

Hope This Helps

---

Give a man a fish:  <%-{-{-{-<

When you say you "find it's too heavy", what makes you think this?

Where in your code is a loop and what do you want to remove?

Note that you can always replace unless(...) by if( not ... ).

Personally, I have the impression that it is not you who finds that code "too heavy" but your teacher or supervisor. Maybe you should go to them and ask them more about what they don't like with your code. Maybe they suggested that you replace the three unless statements with a loop.

If you want to use a loop, I suggest you first print out the three statements and mark with a text marker in one colour the things that are identical between the three statements and then with a text marker of a different colour the things that are different between the three statements. Then you ideally review your course material on loops and find out how you can use a loop to go over the things that are the same and apply the things that need to change for each statement.

Hello Corion. First i haven't got teacher , no longer i mean. Yes it's just a mistake. Obviously, a condition
Lost in translation

You can use loops to iterate over the browsers, though, and you can use variables to avoid fetching the hash values every time:

my @browsers = ('firefox', 'chrome', 'internet explorer');
for my $b1_idx (0 .. $#browsers - 1) {
    my $b1 = $screen{ $browsers[$b1_idx] };
    for my $b2_idx ($b1_idx + 1 .. $#browsers) {
        my $b2 = $screen{ $browsers[$b2_idx] };

        unless ($b1->compare($b2)) {
            my $diff_file = $b1->difference($b2);
            print "#The images are not the same; see $diff_file for de
+tails\n";
            qx{ $diff_file };
        }

    }
}
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Update: missing +1 added.

($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,
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I meaned a condition choroba Loop is a good solution. I must continue to dig which approach could be the best. Thanks
Lost in translation

I try to use your approach. I would like now to get an random element from the list . I did this :

use List::Util qw(shuffle);

my @random_array = shuffle(@browsers);
for my $b1_idx (0 .. $#random_array - 1)
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But it seems to not work. Is it correct or is there an other way to do it ? Thanks in advance !
Lost in translation

What do you mean by "it seems to not work"?

You can help us improve the quality of the answers we're giving by answering the following questions directly in your first post:

What is the exact code you are running? Please show the exact code. This code should be self-sufficient and be shorter than 20 lines.

What is the exact input you are giving? Please show the exact input you are giving to the above program.

What is the output you expect? Please describe the output you expect.

What is the exact output you get? Please show the exact output together with the complete error message(s) that Perl returns you.

Why are you using List::Util? Have you read perlfaq or run perldoc -q random ? This will show you the many frequently asked questions (and their answers) pertaining to getting a random element of an array.

Ok for the update
Lost in translation

unless (...) is the equivalent of if (not (...)) - it only simplifies your code if it makes it more readable. For example, you might find next LINE unless format_is_ok($line); more readable than next LINE if !format_is_ok($line);. When in doubt, stick with if. Also, unless is a conditional statement like if, not a "loop".

unless (...) is the equivalent of if (not (...))

yes this is obviously true, but can be error prone in the case of complex conditions.

De_Morgan's_laws are useful in this case to do the correct translation between the plain and the negated form of a (possibly comlpex) condition.

I was suggested to investigate such laws when i had an Untillian Headache

L*

There are no rules, there are no thumbs..
Reinvent the wheel, then learn The Wheel; may be one day you reinvent one of THE WHEELS.

Oh yes ! I did a big mistake. INdeed, it's a conditionnal and not a loop..end of week Thanks , i changed it in my post edit
Lost in translation

When you update your post: use strike tags and then put in correction. If you change the question mid-stream, posts to the original question are confusing. Make this update explicit.

And yes "unless" is just the "NOT of if". These are all the "same".

#!/usr/bin/perl
use strict;
use warnings;

my $x = 5;
print "x not 3\n" unless $x==3;

print "x not 3\n" if $x!=3;
print "x not 3\n" if !($x==3);
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Usually the "if version" is more clear. However in the above, since $x is seldom exactly 3, "unless" focuses on the usual action with Perl's ability to put the "action" first and the conditional last. For longer blocks, most often use some form of "if".