module data.note; public import data.model : Note; interface NoteDataSource { Note createNote(string username, ulong noteListId, string content); Note updateNote(string username, ulong id, Note newData); void deleteNote(string username, ulong id); ulong countNotes(string username); ulong countNotes(string username, ulong noteListId); } static NoteDataSource noteDataSource; static this() { import data.impl.note; noteDataSource = new SqliteNoteDataSource(); }