merge some duplicated code in parsing song formats

src/conv.cpp

@@ -144,6 +144,45 @@ mpd_tag_type IntoTagItem(char c)
 	}
 }
 
+MPD::Song::GetFunction toGetFunction(char c)
+{
+	switch (c)
+	{
+		case 'l':
+			return &MPD::Song::GetLength;
+		case 'D':
+			return &MPD::Song::GetDirectory;
+		case 'f':
+			return &MPD::Song::GetName;
+		case 'a':
+			return &MPD::Song::GetArtist;
+		case 'A':
+			return &MPD::Song::GetAlbumArtist;
+		case 'b':
+			return &MPD::Song::GetAlbum;
+		case 'y':
+			return &MPD::Song::GetDate;
+		case 'n':
+			return &MPD::Song::GetTrackNumber;
+		case 'N':
+			return &MPD::Song::GetTrack;
+		case 'g':
+			return &MPD::Song::GetGenre;
+		case 'c':
+			return &MPD::Song::GetComposer;
+		case 'p':
+			return &MPD::Song::GetPerformer;
+		case 'd':
+			return &MPD::Song::GetDisc;
+		case 'C':
+			return &MPD::Song::GetComment;
+		case 't':
+			return &MPD::Song::GetTitle;
+		default:
+			return 0;
+	}
+}
+
 #ifdef HAVE_TAGLIB_H
 MPD::Song::SetFunction IntoSetFunction(mpd_tag_type tag)
 {

src/conv.h

@@ -52,6 +52,8 @@ NCurses::Color IntoColor(const std::string &);
 
 mpd_tag_type IntoTagItem(char);
 
+MPD::Song::GetFunction toGetFunction(char c);
+
 #ifdef HAVE_TAGLIB_H
 MPD::Song::SetFunction IntoSetFunction(mpd_tag_type);
 #endif // HAVE_TAGLIB_H

src/display.cpp

@@ -188,56 +188,7 @@ void Display::SongsInColumns(const MPD::Song &s, void *data, Menu<MPD::Song> *me
 		std::string tag;
 		for (size_t i = 0; i < it->type.length(); ++i)
 		{
-			switch (it->type[i])
-			{
-				case 'l':
-					get = &MPD::Song::GetLength;
-					break;
-				case 'D':
-					get = &MPD::Song::GetDirectory;
-					break;
-				case 'f':
-					get = &MPD::Song::GetName;
-					break;
-				case 'a':
-					get = &MPD::Song::GetArtist;
-					break;
-				case 'A':
-					get = &MPD::Song::GetAlbumArtist;
-					break;
-				case 'b':
-					get = &MPD::Song::GetAlbum;
-					break;
-				case 'y':
-					get = &MPD::Song::GetDate;
-					break;
-				case 'n':
-					get = &MPD::Song::GetTrackNumber;
-					break;
-				case 'N':
-					get = &MPD::Song::GetTrack;
-					break;
-				case 'g':
-					get = &MPD::Song::GetGenre;
-					break;
-				case 'c':
-					get = &MPD::Song::GetComposer;
-					break;
-				case 'p':
-					get = &MPD::Song::GetPerformer;
-					break;
-				case 'd':
-					get = &MPD::Song::GetDisc;
-					break;
-				case 'C':
-					get = &MPD::Song::GetComment;
-					break;
-				case 't':
-					get = &MPD::Song::GetTitle;
-					break;
-				default:
-					break;
-			}
+			get = toGetFunction(it->type[i]);
 			tag = get ? s.GetTags(get) : "";
 			if (!tag.empty())
 				break;

src/song.cpp

@@ -372,56 +372,10 @@ std::string MPD::Song::ParseFormat(std::string::const_iterator &it, const char *
 		{
 			switch (*++it)
 			{
-				case 'l':
-					get = &MPD::Song::GetLength;
-					break;
-				case 'D':
-					get = &MPD::Song::GetDirectory;
-					break;
-				case 'f':
-					get = &MPD::Song::GetName;
-					break;
-				case 'a':
-					get = &MPD::Song::GetArtist;
-					break;
-				case 'A':
-					get = &MPD::Song::GetAlbumArtist;
-					break;
-				case 'b':
-					get = &MPD::Song::GetAlbum;
-					break;
-				case 'y':
-					get = &MPD::Song::GetDate;
-					break;
-				case 'n':
-					get = &MPD::Song::GetTrackNumber;
-					break;
-				case 'N':
-					get = &MPD::Song::GetTrack;
-					break;
-				case 'g':
-					get = &MPD::Song::GetGenre;
-					break;
-				case 'c':
-					get = &MPD::Song::GetComposer;
-					break;
-				case 'p':
-					get = &MPD::Song::GetPerformer;
-					break;
-				case 'd':
-					get = &MPD::Song::GetDisc;
-					break;
-				case 'C':
-					get = &MPD::Song::GetComment;
-					break;
-				case 't':
-					get = &MPD::Song::GetTitle;
-					break;
 				case '%':
 					result += *it; // no break here
 				default:
-					get = 0;
-					break;
+					get = toGetFunction(*it);
 			}
 			if (get)
 			{