Upgraded code to switch to C++17. Tested on Debian Buster

src/metadata/AvFormat.cpp

@@ -29,21 +29,21 @@ namespace MetaData
 
 using MetadataMap = std::map<std::string, std::string>;
 
-boost::optional<std::string>
+std::optional<std::string>
 findFirstValueOf(const MetadataMap& metadataMap, std::initializer_list<std::string> tags)
 {
 	auto it = std::find_first_of(std::cbegin(metadataMap), std::cend(metadataMap), std::cbegin(tags), std::cend(tags), [](const auto& it, const auto& str) { return it.first == str; });
 	if (it == std::cend(metadataMap))
-		return boost::none;
+		return std::nullopt;
 
 	return stringTrim(it->second);
 }
 
 static
-boost::optional<Album>
+std::optional<Album>
 getAlbum(const MetadataMap& metadataMap)
 {
-	boost::optional<Album> res;
+	std::optional<Album> res;
 
 	auto album {findFirstValueOf(metadataMap, {"ALBUM"})};
 	if (!album)
@@ -115,8 +115,8 @@ getArtists(const MetadataMap& metadataMap)
 	return artists;
 }
 
-boost::optional<Track>
-AvFormat::parse(const boost::filesystem::path& p, bool debug)
+std::optional<Track>
+AvFormat::parse(const std::filesystem::path& p, bool debug)
 {
 	Track track;
 
@@ -215,7 +215,7 @@ AvFormat::parse(const boost::filesystem::path& p, bool debug)
 	}
 	catch(Av::MediaFileException& e)
 	{
-		return boost::none;
+		return std::nullopt;
 	}
 
 	return track;

src/metadata/AvFormat.hpp

@@ -19,9 +19,6 @@
 
 #pragma once
 
-#include <map>
-#include <string>
-
 #include "MetaData.hpp"
 
 namespace MetaData
@@ -31,7 +28,7 @@ namespace MetaData
 class AvFormat : public Parser
 {
 	public:
-		boost::optional<Track> parse(const boost::filesystem::path& p, bool debug = false) override;
+		std::optional<Track> parse(const std::filesystem::path& p, bool debug = false) override;
 };
 
 } // namespace MetaData

src/metadata/MetaData.hpp

@@ -20,12 +20,11 @@
 #pragma once
 
 #include <chrono>
+#include <filesystem>
 #include <map>
+#include <optional>
 #include <set>
 
-#include <boost/optional.hpp>
-#include <boost/filesystem.hpp>
-
 namespace MetaData
 {
 	using Clusters = std::map<std::string /* type */, std::set<std::string> /* names */>;
@@ -54,15 +53,15 @@ namespace MetaData
 		std::string			title;
 		std::string			musicBrainzTrackID;
 		std::string			musicBrainzRecordID;
-		boost::optional<Album>		album;
+		std::optional<Album>		album;
 		Clusters			clusters;
 		std::chrono::milliseconds 	duration {};
-		boost::optional<std::size_t>	trackNumber;
-		boost::optional<std::size_t>	totalTrack;
-		boost::optional<std::size_t>	discNumber;
-		boost::optional<std::size_t>	totalDisc;
-		boost::optional<int>		year;
-		boost::optional<int>		originalYear;
+		std::optional<std::size_t>	trackNumber;
+		std::optional<std::size_t>	totalTrack;
+		std::optional<std::size_t>	discNumber;
+		std::optional<std::size_t>	totalDisc;
+		std::optional<int>		year;
+		std::optional<int>		originalYear;
 		bool				hasCover {false};
 		std::vector<AudioStream>	audioStreams;
 		std::string			acoustID;
@@ -73,7 +72,7 @@ namespace MetaData
 	class Parser
 	{
 		public:
-			virtual boost::optional<Track> parse(const boost::filesystem::path& p, bool debug = false) = 0;
+			virtual std::optional<Track> parse(const std::filesystem::path& p, bool debug = false) = 0;
 
 			void setClusterTypeNames(const std::set<std::string>& clusterTypeNames) { _clusterTypeNames = clusterTypeNames; }
 

src/metadata/TagLibParser.cpp

@@ -126,10 +126,10 @@ getAlbumArtists(const TagLib::PropertyMap& properties)
 }
 
 static
-boost::optional<Album>
+std::optional<Album>
 getAlbum(const TagLib::PropertyMap& properties)
 {
-	boost::optional<Album> res;
+	std::optional<Album> res;
 
 	std::vector<std::string> albumName {getPropertyValues(properties, "ALBUM")};
 	if (albumName.empty())
@@ -145,8 +145,8 @@ getAlbum(const TagLib::PropertyMap& properties)
 	return res;
 }
 
-boost::optional<Track>
-TagLibParser::parse(const boost::filesystem::path& p, bool debug)
+std::optional<Track>
+TagLibParser::parse(const std::filesystem::path& p, bool debug)
 {
 	TagLib::FileRef f {p.string().c_str(),
 			true, // read audio properties
@@ -155,13 +155,13 @@ TagLibParser::parse(const boost::filesystem::path& p, bool debug)
 	if (f.isNull())
 	{
 		LMS_LOG(METADATA, ERROR) << "File '" << p.string() << "': parsing failed";
-		return boost::none;
+		return std::nullopt;
 	}
 
 	if (!f.audioProperties())
 	{
 		LMS_LOG(METADATA, INFO) << "File '" << p.string() << "': no audio properties";
-		return boost::none;
+		return std::nullopt;
 	}
 
 	Track track;

src/metadata/TagLibParser.hpp

@@ -19,9 +19,6 @@
 
 #pragma once
 
-#include <map>
-#include <string>
-
 #include "MetaData.hpp"
 
 namespace MetaData
@@ -31,7 +28,7 @@ namespace MetaData
 class TagLibParser : public Parser
 {
 	public:
-		boost::optional<Track> parse(const boost::filesystem::path& p, bool debug = false) override;
+		std::optional<Track> parse(const std::filesystem::path& p, bool debug = false) override;
 };
 
 } // namespace MetaData