You need a little more to get this to work from a web server. Here is a more complete demo incorporating ideas from other replies. Try playing around with the code until you understand what's happening. Also, it is ok to execute code outside of a module's subs depending on what you're trying to achieve. 

package foo;
use strict;
use warnings;

require Exporter;
our @ISA = 'Exporter';
our @EXPORT = 'bar';

print "module foo loaded here \n";

sub bar{
    print "module foo, sub bar executed here\n";
}
1;

[download]
#!/usr/bin/perl
use strict;
use warnings;

print "main I \n";

# sub called from module
bar();

# begin blocks are loaded at compile time
# the first BEGIN block will be the first thing to execute
BEGIN {

    # turn on autoflush so you will see print results immediately
    $| = 1;
 
    # plain text header to simplify the print statements for this demo
    print "content-type: text/plain\n\n";

    print "begin block 1 \n";
}

print "main II \n";

# modules are also loaded at compile time
# consider them to behave like BEGIN blocks
use foo;

print "main III \n";

BEGIN {
   print "begin block 2 \n";
}

[download]

In reply to Re^3: when is a perl module executed? by hangon
in thread when is a perl module executed? by ketaki

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