use strict;
use warnings;
use Data::Dumper;
use Config::General;

my $c = Config::General->new(
  -ConfigFile      => \*DATA,
  -InterPolateVars => 1,
);

print Dumper {$c->getall()};

__DATA__
V1=/home/user
V2=$V1/test
V3=$V2/file.txt