Also, people have suggested that you turn on warnings, but they fail to mention that you should do some checking of $guess (to see whether it's a number) before comparing it to $secret_number - otherwise, you will get warnings.

#!/usr/bin/perl

use strict;
use warnings;

my $secret = 1 + int rand 100;

while (print "Your guess > ") {
    local $_ = <>;
    chomp;

    if (!/\S/ || /quit/i || /exit/i) {
        print "Too bad, you gave up.\n";
        exit;
    }

    if (/\D/) {
        print "You didn't enter a non-negative integer\n";
        next;
    }

    if ($_ == $secret) {
        print "You guessed the number correctly.\n";
        exit;
    }

    my $answer = $_ < $secret ? "less" : "greater";

    print "The number you entered is $answer than the secret number\n"
+;
}

__END__
[download]

That's how I would do it.

Abigail

That is very, very nice.

It's not to say your code is perfect, and there are a number of minor nits and points of style I'd probably give. However, rather than overload you with suggestions that have historical and/or religious subtleties, I'll skip all that.

--
[ e d @ h a l l e y . c c ]

my $guess = 0; # can't be the right one then
until($guess == $secret_number)
{
   $guess = <STDIN>;
   # do the rest
}
[download]

Like Abigail and others say, there are ways to improve your code. But as far as being different from Randall's textbook codee, there's nothing wrong. After all, your code works correctly, right?

Bonus points for using unless. People are often intimidated by unless or just don't see the opportunity to use it appropriately.

When you finish a chunk of code, it's worth looking at it to see to see what is clumsy, what can be simplified. In this case, for example, you order the contents of the loop so that detecting 'quit' and exiting the loop happens at the bottom ... because you started with until ($guess eq $secret_number ) { . If the user plays to completion, the exit happens at the top, but if they give it, the loop is exited due to last. Neither is better or more natural than the other, so it's worth considering rotating the loop to natural order: prompt, input, test input, test input, output message.

until ($guess eq $secret_number) {
    print "\nEnter a number between 1 and 100 : ";
    chomp($guess = <STDIN>);
    if ($guess =~ /quit|exit|^\s*$/i) {
        $quit = "yes";
        last
    }
    my $answer = ($guess < $secret_number) ? "less than" :
                 ($guess > $secret_number) ? "greater than":
                                             "";
   print "\nThe number you entered is $answer the secret number.\n";
}
[download]

Yes, you exit in the middle of the loop, nothing wrong with that. In some languages exiting a loop is tricky, but it's easy in Perl. You were already using last, anyway.

The next complicated structure is the regex and exit. Look at the artificial variable, $quit. Instead of using the variable, you could move the printed message into the regex condition.

Hmm .... it's beginning to look like Abigail's solution.

Your code works. Once you have code that works, Then you can make it work better, do more, more effectively communicate what you consider important.

--
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