Using constants...

[willjones]

I want to have a file where I define a set of constants and then be able to require that file from others and have those constants available. For some reason though I can't seem to get this to work. I have something like this setup...

constants.pl

use constant 
    {
        MY_CONSTANT1 => 1,
        MY_CONSTANT2 => 2,
        MY_CONSTANT3 => 3,
        MY_CONSTANT4 => 4
    };

sub useConstants
{
   #able to use constants fine in here...
   my $var = MY_CONSTANT4;
   print "$var\n"; #outputs '4'
}

1;

main.pl

#!/usr/bin/perl

#use strict;  # If I uncomment this line it won't compile because it c
+laims MY_CONSTANT3 is a bareword and not a constant.

require "constants.pl";

#if I call useConstants this sub can use them just fine.
useConstants();

#However if I try to use a constant that should've been defined in con
+stants.pl here it won't work!
my $var = MY_CONSTANT3;
print "$var\n"; #outputs 'MY_CONSTANT3'  !!  Why won't it output '3'?

exit 1;

output...

me@mybox:/test
>perl main.pl
4
MY_CONSTANT3
me@mybox:/test
>

If I add a use strict; in to the top of main.pl this won't even compile because it says MY_CONSTANT3 is a bareword and isn't allowed. I don't understand. Isn't constants.pl in the main namespace too? Why wouldn't it still be visible? What can I do to accomplish having a set of constants that can be shared across multiple files?
Thanks,