$config::fee="FEE"
$config::fi="FI"
$config::fo="FO"
@config::fum=qw / fee fi fo fum /

##</code><code>##

my $namespace = "here";
while (<DAT>) {
    s/([\$\@\%])/$1$namespace\::/;
    eval $_;
}

##</code><code>##

# config:
{
  fee=>"FEE",
  fi=>"FI",
  fo=>"FO",
  fum=>[qw/ fee fi fo fum /],
}

##</code><code>##

my $config_hr = do 'datafile.txt';