use strict;
use warnings;

BEGIN {
	package MyVars;
	use Exporter::Shiny;
	use B::Hooks::Parser;
	
	our $pi = 3.14195;
	sub import {
		B::Hooks::Parser::inject(sprintf('my $pi; BEGIN { $pi = $%s::pi };', __PACKAGE__));
	}
};

use Data::Dumper;

my $pi = 3;

{
	use MyVars;
	print Dumper($pi);
}

print Dumper($pi);