db/Interface: migrate visitor methods from class Error to C++ exceptions

1 files changed, 12 insertions, 17 deletions

diff --git a/src/db/Interface.hxx b/src/db/Interface.hxx
index 625328b42..6ad9560d6 100644
--- a/src/db/Interface.hxx
+++ b/src/db/Interface.hxx
@@ -84,36 +84,31 @@ public:
 	/**
 	 * Visit the selected entities.
 	 */
-	virtual bool Visit(const DatabaseSelection &selection,
+	virtual void Visit(const DatabaseSelection &selection,
 			   VisitDirectory visit_directory,
 			   VisitSong visit_song,
-			   VisitPlaylist visit_playlist,
-			   Error &error) const = 0;
+			   VisitPlaylist visit_playlist) const = 0;
 
-	bool Visit(const DatabaseSelection &selection,
+	void Visit(const DatabaseSelection &selection,
 		   VisitDirectory visit_directory,
-		   VisitSong visit_song,
-		   Error &error) const {
-		return Visit(selection, visit_directory, visit_song,
-			     VisitPlaylist(), error);
+		   VisitSong visit_song) const {
+		Visit(selection, visit_directory, visit_song, VisitPlaylist());
 	}
 
-	bool Visit(const DatabaseSelection &selection, VisitSong visit_song,
-		   Error &error) const {
-		return Visit(selection, VisitDirectory(), visit_song, error);
+	void Visit(const DatabaseSelection &selection,
+		   VisitSong visit_song) const {
+		return Visit(selection, VisitDirectory(), visit_song);
 	}
 
 	/**
 	 * Visit all unique tag values.
 	 */
-	virtual bool VisitUniqueTags(const DatabaseSelection &selection,
+	virtual void VisitUniqueTags(const DatabaseSelection &selection,
 				     TagType tag_type, tag_mask_t group_mask,
-				     VisitTag visit_tag,
-				     Error &error) const = 0;
+				     VisitTag visit_tag) const = 0;
 
-	virtual bool GetStats(const DatabaseSelection &selection,
-			      DatabaseStats &stats,
-			      Error &error) const = 0;
+	gcc_pure
+	virtual DatabaseStats GetStats(const DatabaseSelection &selection) const = 0;
 
 	/**
 	 * Update the database.  Returns the job id on success, 0 on