Prefer "parent" to "base" since the former is lighter and part
of Perl 5.10+. We'll also rely on warnings from "-w" globally
(or not) instead of via "use".
# This writes to the search index.
package PublicInbox::SearchIdx;
use strict;
-use warnings;
-use base qw(PublicInbox::Search PublicInbox::Lock);
+use v5.10.1;
+use parent qw(PublicInbox::Search PublicInbox::Lock);
use PublicInbox::Eml;
use PublicInbox::InboxWritable;
use PublicInbox::MID qw/mid_clean mid_mime mids_for_index/;