hval: export prurl and add prototype

This allows to do some compile-time checking and fills in a
missing "use" in PublicInbox::NewsWWW, allowing it to be used
standalone and independently of PublicInbox::WWW

1 files changed, 3 insertions, 2 deletions

diff --git a/lib/PublicInbox/Hval.pm b/lib/PublicInbox/Hval.pm
index cd3a4df3..7e007027 100644
--- a/lib/PublicInbox/Hval.pm
+++ b/lib/PublicInbox/Hval.pm
@@ -10,7 +10,7 @@ use Encode qw(find_encoding);
 use PublicInbox::MID qw/mid_clean mid_escape/;
 use base qw/Exporter/;
 our @EXPORT_OK = qw/ascii_html obfuscate_addrs to_filename src_escape
-                to_attr from_attr/;
+                to_attr from_attr prurl/;
 my $enc_ascii = find_encoding('us-ascii');
 
 # safe-ish acceptable filename pattern for portability
@@ -84,7 +84,8 @@ sub raw {
         }
 }
 
-sub prurl {
+# returns a protocol-relative URL string
+sub prurl ($$) {
         my ($env, $u) = @_;
         if (ref($u) eq 'ARRAY') {
                 my $h = $env->{HTTP_HOST} // $env->{SERVER_NAME};