sub create_selector {
  my ($spec) = @_;
  my $selector;
  if ($spec =~ m/^=(.*)/) {
    $selector = sub { $_[0]->version eq $1 }
  } elsif ($spec =~ m/!=(.*)/) {
    $selector = sub { $_[0]->version ne $1 }
  } elsif ($spec =~ m/>(.*)/) {
    $selector = sub { $_[0]->version gt $1 }
  }
  $selector;
}

my $selector = create_selector("=6.2");
...
my @selected_dists = grep { $selector->{$_} } @list_of_dists;