Firstly you will need to have all of that in a BEGIN block in order for @EXPORT_OK to have the values in it when import is called by the use gen_var.

Also I would eschew the second eval and simply do something likeL

BEGIN
{
   foreach my $variable (@variables) {
       eval "our \$$variable = $counter; push    \@exported_symbols, \
+$$variable";
   $counter++;
   push @EXPORT_OK, "\$$variable";
   }
}
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I do something similar in Sys::Utmp for what it's worth. Actually it's worse because there I export the symbols into one module that then exports them to the callers namespace :-O

/J\