[WIP] searchidx: use "++" overloading in Search::Xapian::PostingIterator

[Eric Wong <e@80x24.org>]

This makes it easier to be compatible with the SWIG-generated
"Xapian" bindings, which are currently lacking the "->inc" sub
implemented in the XS binding.

No plans to apply this to master, just yet.

My goal is to be compatible with both Search::Xapian XS
and the "Xapian" SWIG binding as long as possible; but the
SWIG binding is still not ready for prime-time, yet.

cf. https://trac.xapian.org/ticket/523
---
 lib/PublicInbox/SearchIdx.pm | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/PublicInbox/SearchIdx.pm b/lib/PublicInbox/SearchIdx.pm
index 665f673..eb59d0d 100644
--- a/lib/PublicInbox/SearchIdx.pm
+++ b/lib/PublicInbox/SearchIdx.pm
@@ -382,7 +382,7 @@ sub batch_do {
 		my ($head, $tail) = $self->find_doc_ids($termval);
 		return if $head == $tail;
 		my @ids;
-		for (; $head != $tail && @ids < $batch_size; $head->inc) {
+		for (; $head != $tail && @ids < $batch_size; $head++) {
 			push @ids, $head->get_docid;
 		}
 		$cb->(\@ids);
@@ -437,7 +437,7 @@ sub remove_by_oid {
 	# there is only ONE element in @delete unless we
 	# have bugs in our v2writable deduplication check
 	my @delete;
-	for (; $head != $tail; $head->inc) {
+	for (; $head != $tail; $head++) {
 		my $docid = $head->get_docid;
 		my $doc = $db->get_document($docid);
 		my $smsg = PublicInbox::SearchMsg->wrap($mid);
-- 
EW