Use value equality collections in order to do equality on records

Timetable/Line.cs

@@ -1,4 +1,5 @@
 using System.Diagnostics;
+using LanguageExt;
 
 namespace Timetable;
 
@@ -14,25 +15,25 @@ public partial record Line
     /// </summary>
     public required string Name { get; init; }
 
-    private readonly Route[] _routes = null!; // Will be set by *required* init-er below.
+    private readonly Arr<Route> _routes = null!; // Will be set by *required* init-er below.
 
     /// <summary>
     /// All <see cref="Line.Route"/>s assigned to this <see cref="Line"/>.
     /// </summary>
-    public required Route[] Routes
+    public required IReadOnlyList<Route> Routes
     {
         get => _routes;
         init
         {
-            _routes = value;
-            foreach (var route in Routes)
+            foreach (var route in value)
             {
                 route.Line = this;
                 // Validate that stop distances length matches route length.
                 Debug.Assert(
                     route.TimeProfiles.All(profile => profile.StopDistances.Length == route.StopPositions.Length - 1),
                     $"For {this.Name}, {route.ToString()}, at least one time profile has an incorrect stop distance count.");
             }
+            _routes = Arr.createRange(value);
         }
     }
 
@@ -82,10 +83,16 @@ public required Route[] Routes
     public IEnumerable<Trip> TripsOfRouteIndex(Index routeIndex) =>
         Trips.Where(trip => trip.Route == Routes[routeIndex]);
 
+    private readonly Arr<TripCreate> _tripsCreate = null!; // Will be set by *required* init-er below.
+
     /// <summary>
     /// All <see cref="TripCreate"/>s used to specify which <see cref="Line.Trip"/>s exist for this <see cref="Line"/>.
     /// </summary>
-    public required ICollection<TripCreate> TripsCreate { get; init; }
+    public required IReadOnlyList<TripCreate> TripsCreate
+    {
+        get => _tripsCreate;
+        init => _tripsCreate = Arr.createRange(value);
+    }
 
     /// <summary>
     /// Which medium of transportation is the one used by this <see cref="Line"/>.
@@ -102,10 +109,16 @@ public IEnumerable<Trip> TripsOfRouteIndex(Index routeIndex) =>
     /// </summary>
     public IEnumerable<Route> MainRoutes => MainRouteIndices.Select(index => Routes[index]);
 
+    private readonly Arr<Index> _mainRouteIndices = null!; // Will be set by *required* init-er below.
+
     /// <summary>
-    /// Specifies the indices of the <see cref="Line.Route"/>s that are considers <see cref="MainRoutes"/>.
+    /// Specifies the indices of the <see cref="Line.Route"/>s that are considered <see cref="MainRoutes"/>.
     /// </summary>
-    public required Index[] MainRouteIndices { get; init; }
+    public required IReadOnlyList<Index> MainRouteIndices
+    {
+        get => _mainRouteIndices;
+        init => _mainRouteIndices = Arr.createRange(value);
+    }
 
     /// <summary>
     /// <see cref="Line.Route"/>s that are considered to be representative <see cref="Line.Route"/>s for this <see cref="Line"/>.
@@ -115,15 +128,28 @@ public IEnumerable<Trip> TripsOfRouteIndex(Index routeIndex) =>
     /// </summary>
     public IEnumerable<Route> OverviewRoutes => OverviewRouteIndices.Select(index => Routes[index]);
 
+    private readonly Arr<Index> _overviewRouteIndices = null!; // Will be set by *required* init-er below.
+
     /// <summary>
     /// Specifies the indices of the <see cref="Line.Route"/>s that are considers <see cref="OverviewRoutes"/>.
     /// </summary>
-    public required Index[] OverviewRouteIndices { get; init; }
+    public required IReadOnlyList<Index> OverviewRouteIndices
+    {
+        get => _overviewRouteIndices;
+        init => _overviewRouteIndices = Arr.createRange(value);
+    }
+
+    private readonly HashMap<string, string> _annotations = HashMap<string, string>.Empty;
 
     /// <summary>
     /// Manual annotations, indexed by their symbol, mapping to their text.
     /// </summary>
-    public Dictionary<string, string> Annotations { get; init; } = new();
+    // TODO: Find a better way here, potentially with a native value equality dictionary.
+    public IReadOnlyDictionary<string, string> Annotations
+    {
+        get => _annotations.ToReadOnlyDictionary();
+        init => _annotations = HashMap.createRange(value);
+    }
 
     /// <summary>
     /// The typical time of day where this <see cref="Line"/> operates.

Timetable/Route.cs

@@ -1,3 +1,8 @@
+using System.Diagnostics.Contracts;
+using System.Numerics;
+using System.Runtime.CompilerServices;
+using LanguageExt;
+
 namespace Timetable;
 
 public partial record Line
@@ -15,15 +20,27 @@ public partial record Route
 
         internal Line? Line { get; set; }
 
+        private readonly Arr<Stop.Position> _stopPositions = null!; // Will be set by *required* init-er below.
+
         /// <summary>
         /// The <see cref="Stop.Position"/>s where this route calls at.
         /// </summary>
-        public required Stop.Position[] StopPositions { get; init; }
+        public required IReadOnlyList<Stop.Position> StopPositions
+        {
+            get => _stopPositions;
+            init => _stopPositions = Arr.createRange(value);
+        }
+
+        private readonly Arr<TimeProfile> _timeProfiles = null!; // Will be set by *required* init-er below.
 
         /// <summary>
         /// All the existing timing patterns for this route.
         /// </summary>
-        public required TimeProfile[] TimeProfiles { get; init; }
+        public required IReadOnlyList<TimeProfile> TimeProfiles
+        {
+            get => _timeProfiles;
+            init => _timeProfiles = Arr.createRange(value);
+        }
 
         /// <summary>
         /// A text to be displayed alongside this route.
@@ -93,7 +110,7 @@ public bool TryGetIndexOfStopFirst(Stop stop, out int index)
         /// <param name="stop">The <see cref="Stop"/> to check for.</param>
         /// <param name="onlyDepartures">Only consider departures, i.e. the last stop of this route is ignored.</param>
         public bool DoesStopAt(Stop stop, bool onlyDepartures) => StopPositions
-            .Take(StopPositions.Length - (onlyDepartures
+            .Take(StopPositions.Count - (onlyDepartures
                 ? /* when we only want departures, the last stop is no longer relevant */ 1
                 : 0)).Select(pos => pos.Stop).Contains(stop);
 
@@ -168,11 +185,16 @@ public Route WithoutStop(Stop stopToExclude) => StopPositions.Any(pos => pos.Sto
         /// if those two stations exist and are next to each other.
         /// </summary>
         /// <returns></returns>
-        public Route WithStopBetween(Stop before, Stop.Position inserted, Stop after, TimeSpan firstTime, TimeSpan secondTime)
+        public Route WithStopBetween(Stop before, Stop.Position inserted, Stop after, TimeSpan firstTime,
+            TimeSpan secondTime)
         {
-            var beforeIndex = Array.IndexOf(StopPositions, before);
+            List<int> list = [1, 2, 3];
+            IReadOnlyList<int> d = list;
+            var x = list[1..];
+            Console.WriteLine(x.Count);
+            var beforeIndex = StopPositions.IndexOf(before);
             if (beforeIndex == -1) return this;
-            var afterIndex = Array.IndexOf(StopPositions, after);
+            var afterIndex = StopPositions.IndexOf(after);
             if (afterIndex == -1) return this;
             if (afterIndex != beforeIndex + 1) return this;
             Stop.Position[] insertedPositions =
@@ -206,3 +228,13 @@ public Route WithStopBetween(Stop before, Stop.Position inserted, Stop after, Ti
             .Select(trip => int.PopCount((int)(trip.DaysOfOperation & days))).Sum();
     }
 }
+
+file static class CollectionExtensions
+{
+    [Pure]
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public static int IndexOf<T>(this IReadOnlyList<T> list, T element) where T : IEqualityOperators<T, T, bool> =>
+        list is Arr<T> arr
+            ? arr.IndexOf(element)
+            : list.Index().Where(tuple => tuple.Item == element).Select(tuple => tuple.Index).FirstOrDefault(-1);
+}

Timetable/Stop.cs

@@ -1,3 +1,5 @@
+using R4Utils.ValueEqualityCollections;
+
 namespace Timetable;
 
 /// <summary>
@@ -19,10 +21,19 @@ public Stop()
     /// </summary>
     public required string InitialName { private get; init; }
 
+    private readonly ValueEqualityCollection<(DateOnly Date, string Name), List<(DateOnly Date, string Name)>>
+        _nameChanges = null!; // Will be set by *required* init-er below.
+
     /// <summary>
     /// Maps the <see cref="DateOnly"/> of a change of name of this <see cref="Stop"/> to its new name.
     /// </summary>
-    public List<(DateOnly Date, string Name)> NameChanges { get; init; } = [];
+    public List<(DateOnly Date, string Name)> NameChanges
+    {
+        get => _nameChanges.Underlying;
+        init => _nameChanges =
+            value.AsGenericOrderedValueEqualityCollection<(DateOnly Date, string Name),
+                List<(DateOnly Date, string Name)>>();
+    }
 
     /// <summary>
     /// The <see cref="City"/> of this <see cref="Stop"/>.
@@ -49,18 +60,19 @@ public string NameAt(DateOnly date) => NameChanges.Count == 0 || NameChanges[0].
     private string DisplayNameFor(string name, City referenceCity) =>
         referenceCity == City ? name : $"{City.Name}, {name}";
 
-    private readonly Position[] _positions = null!; // Will be set below.
+    private readonly ValueEqualityCollection<Position, Position[]> _positions =
+        Array.Empty<Position>().AsGenericOrderedValueEqualityCollection<Position, Position[]>();
 
     /// <summary>
     /// All <see cref="Position"/>s of this <see cref="Stop"/>.
     /// </summary>
     /// <remarks>Defaults to a single-element array if omitted.</remarks>
     public /*required*/ Position[] Positions
     {
-        get => _positions;
+        get => _positions.Underlying;
         init
         {
-            _positions = value;
+            _positions = value.AsGenericOrderedValueEqualityCollection<Position, Position[]>();
             foreach (var position in _positions)
             {
                 if (position.Stop is not null)

Timetable/TimeProfile.cs

@@ -1,3 +1,5 @@
+using R4Utils.ValueEqualityCollections;
+
 namespace Timetable;
 
 public partial record Line
@@ -11,10 +13,17 @@ public partial record Route
         /// </summary>
         public record TimeProfile
         {
+            private readonly ValueEqualityCollection<TimeSpan, TimeSpan[]>
+                _stopDistances = null!; // Will be set by *required* init-er below.
+
             /// <summary>
             /// At index <c>i</c> there is the time it takes to travel from stop position <c>i</c> to <c>i+1</c>.
             /// </summary>
-            public required TimeSpan[] StopDistances { get; init; }
+            public required TimeSpan[] StopDistances
+            {
+                get => _stopDistances.Underlying;
+                init => _stopDistances = value.AsGenericOrderedValueEqualityCollection<TimeSpan, TimeSpan[]>();
+            }
 
             /// <summary>
             /// Get the time it takes to travel from stop index <paramref name="fromIndex"/> to <paramref name="toIndex"/>.

Timetable/Timetable.csproj

@@ -15,4 +15,8 @@
       <DocumentationFile>bin\Release\net8.0\Timetable.xml</DocumentationFile>
     </PropertyGroup>
 
+    <ItemGroup>
+      <PackageReference Include="LanguageExt.Core" Version="4.4.9" />
+    </ItemGroup>
+
 </Project>

Timetable/Trip.cs

@@ -1,3 +1,5 @@
+using LanguageExt;
+
 namespace Timetable;
 
 public partial record Line
@@ -32,25 +34,37 @@ public partial record Trip
         /// </summary>
         public required DaysOfOperation DaysOfOperation { get; init; }
 
+        private readonly Arr<ManualAnnotation> _annotations = null!; // Will be set by *required* init-er below.
+
         /// <summary>
         /// All manually (in the timetable) specified <see cref="ManualAnnotation"/> for this <see cref="Trip"/>.
         /// </summary>
-        public required List<ManualAnnotation> Annotations { get; init; }
+        public required IReadOnlyList<ManualAnnotation> Annotations
+        {
+            get => _annotations;
+            init => _annotations = Arr.createRange(value);
+        }
+
+        private readonly Arr<TripCreate.Connection> _connections = null!; // Will be set by *required* init-er below.
 
         /// <summary>
         /// All through services this <see cref="Trip"/> participates in.
         /// <br/><br/>
         /// This should have 0 (no through service), 1 (start or end of through service), or 2 (middle of a through service) elements.
         /// </summary>
-        public required List<TripCreate.Connection> Connections { private get; init; }
+        public required IReadOnlyList<TripCreate.Connection> Connections
+        {
+            private get => _connections;
+            init => _connections = Arr.createRange(value);
+        }
 
         /// <summary>
         /// Translate the trip-create <see cref="Timetable.Line.TripCreate.Connection"/>s present on this <see cref="Trip"/> into trip <see cref="Connection"/>s.
         /// </summary>
         /// <param name="allLines">All <see cref="Line"/>s present in the current network, indexed by their id.</param>
         // Consider adding more validation steps if it becomes a problem.
-        public IEnumerable<Connection> GetConnections(IReadOnlyDictionary<string, Line> allLines) => Connections.Select(
-            connection => new Connection
+        public IEnumerable<Connection> GetConnections(IReadOnlyDictionary<string, Line> allLines) =>
+            Connections.Select(connection => new Connection
             {
                 Type = connection.Type,
                 NotableViaStop = connection.NotableViaStop,

Timetable/TripCreate.cs

@@ -1,3 +1,5 @@
+using LanguageExt;
+
 namespace Timetable;
 
 public partial record Line
@@ -42,20 +44,32 @@ public TripCreate()
         [Obsolete($"Use {nameof(AnnotationSymbols)} instead.", false)]
         public string AnnotationSymbol
         {
-            init => AnnotationSymbols.Add(value);
+            init => _annotationSymbols = Arr.create(value);
         }
 
+        private readonly Arr<string> _annotationSymbols = Arr.empty<string>();
+
         /// <summary>
         /// The symbols (defined as the keys of <see cref="Line.Annotations"/>) of the annotations this trip has.
         /// </summary>
-        public List<string> AnnotationSymbols { get; init; } = [];
+        public IReadOnlyList<string> AnnotationSymbols
+        {
+            get => _annotationSymbols;
+            init => _annotationSymbols = Arr.createRange(value);
+        }
+
+        private readonly Arr<Connection> _connections = Arr.empty<Connection>();
 
         /// <summary>
         /// All through services this trip participates in.
         /// <br/><br/>
         /// This should have 0 (no through service), 1 (start or end of through service), or 2 (middle of a through service) elements.
         /// </summary>
-        public List<Connection> Connections { get; init; } = [];
+        public IReadOnlyList<Connection> Connections
+        {
+            get => _connections;
+            init => _connections = Arr.createRange(value);
+        }
 
         /// <summary>
         /// Repeat this <see cref="TripCreate"/> instance for every <paramref name="interval"/>.

TimetableConsole/Program.cs

@@ -0,0 +1,33 @@
+/*
+
+using System.Diagnostics;
+using Timetable;
+
+var sw = new Stopwatch();
+sw.Start();
+var history = VipTimetable.VipHistory.History;
+var entry = history[0];
+var lines = entry.OrderedLinesById.ToArray();
+var line = lines[0].Value;
+var routes = line.Routes;
+var route = routes[0];
+var trips = line.TripsOfRouteIndex(0).ToArray();
+var stopTimetableView = new Timetable.Views.StopTimetableView(lines.ToDictionary(), trips,
+    [DaysOfOperation.Weekday, DaysOfOperation.Weekend], route.StopPositions[0].Stop, new DateOnly(2024, 1, 3));
+sw.Stop();
+Console.WriteLine($"Got {trips.Length} trips for route {route}.");
+Console.WriteLine($"Last stop of route 0: {stopTimetableView.LastStopOfRoute(0)}");
+Console.WriteLine($"Took {sw.Elapsed}");
+*/
+
+List<int> Test()
+{
+    List<int> list = [1, 2, 3];
+    IReadOnlyList<int> d = list;
+    var x = list[1..];
+    var y = d.Mem
+    return x;
+}
+
+
+Console.WriteLine(Test().Count);