Hi everyone,

I'm not entirely sure what enviroment variables are. Any ideas? What do we use them for? Bear with me, I'm a windows guy (for now) ...

In one of the exercises in "Learning Perl 5th ed." (chapter 15), they use the following: 
my $Verbose = $ENV{VERBOSE} // 1;
my $secret = int(1 + rand 100);

print "Don't tell anyone, but the secret number is $secret.\n" if $Ver
+bose;

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What does this all mean? What's with the "// 1"?

In reply to Environment variables by neutron

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