BEGIN {
    my $varName  = 'SOME_VAR';
    my $varValue = 123;

    ##
    ## Dynamically create the package
    ##

    my $code = qq/
package Somepackage;

use Exporter;
our \@ISA = qw(Exporter);

our \@EXPORT_OK = qw(\$$varName);

our \$$varName = $varValue;

1;
/;

    print $code, "\n";

    eval $code;
    $INC{"Somepackage.pm"} = 'abc';
}

##</code><code>##

BEGIN {
    my $varName  = 'SOME_VAR';
    my $varValue = 123;

    require Exporter;
    $INC{"Somepackage.pm"} = 1;
    package Somepackage;

    our @ISA = qw(Exporter);
    our @EXPORT_OK = $varName;
 
    no strict 'refs';
    $$varName = $varValue;
}