Test generic IEquatable

DummyProject/DummyProject.sln

@@ -0,0 +1,25 @@
+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 17
+VisualStudioVersion = 17.1.32407.343
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{6EC3EE1D-3C4E-46DD-8F32-0CC8E7565705}") = "SmallValueSet", "..\SmallValueSet\SmallValueSet.fsproj", "{3F5A0AE0-8CF7-4853-BE61-CA19155EE9A5}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{3F5A0AE0-8CF7-4853-BE61-CA19155EE9A5}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{3F5A0AE0-8CF7-4853-BE61-CA19155EE9A5}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{3F5A0AE0-8CF7-4853-BE61-CA19155EE9A5}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{3F5A0AE0-8CF7-4853-BE61-CA19155EE9A5}.Release|Any CPU.Build.0 = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+	GlobalSection(ExtensibilityGlobals) = postSolution
+		SolutionGuid = {2F960B42-920E-45EE-B358-662E67BE68B5}
+	EndGlobalSection
+EndGlobal

SmallValueSet/Program.fs

@@ -327,6 +327,88 @@ type SmallSetInt64 (newValues: int64 seq) =
     member _.Values () =
         seq { for i in 0 .. count -> values[i] }
 
+        /// An array backed Set to be used with Value types where the
+/// number of elements is small. It is meant to have an API
+/// that is compatible with the HashSet<'T> collection
+type SmallSetGenericIEquatable<'T when 'T :> System.IEquatable<'T>> (newValues: 'T seq) =
+
+    let mutable count = Seq.length newValues
+    let mutable values = Array.zeroCreate (count * 2)
+    do newValues |> Seq.iteri (fun i v -> values[i] <- v)
+
+    /// Adds an element to the SmallSet and returns a bool
+    /// indicating whether the element was added
+    member _.Add(newValue: 'T) =
+        let mutable exists = false
+        let mutable i = 0
+
+        while i < count && (not exists) do
+            exists <- (values.[i]:>IEquatable<'T>).Equals(newValue)
+            i <- i + 1
+
+        // We only need to add the element if it does not exist
+        if not exists then
+
+            // Check if we have capacity in values to add the value
+            if count < values.Length then
+                // Add the new value to the end
+                values[count] <- newValue
+                // Update the number of elements stored in the SmallSet
+                count <- count + 1
+
+            else
+                // Create a new, larger array to contain the values
+                let newValues = Array.zeroCreate (values.Length * 2)
+                // Add the values from the previous store to the new one
+                values
+                |> Array.iteri (fun i v -> newValues[i] <- v)
+                // Add the new value to the end
+                newValues[values.Length] <- newValue
+                // Update the number of elements held by the SmallSet
+                count <- values.Length + 1
+                // Swap out the internal store
+                values <- newValues
+
+        exists
+
+    /// Removes an element from the SmallSet returning a bool
+    /// indicating whether the SmallSet contained the element
+    member _.Remove(value: 'T) =
+
+        let mutable i = 0
+        let mutable isFound = false
+
+        while i < count && (not isFound) do
+
+            // Check if we have found the value of interest
+            if (values[i]:>IEquatable<'T>).Equals(value) then
+                // We overwrite the removed value with the last value
+                // in the SmallSet
+                values[i] <- values[count - 1]
+                // We decrement the count to indicate the new number of
+                // elements in the small set
+                count <- count - 1
+                // We update the isFound flag to break out of the loop
+                isFound <- true
+
+            i <- i + 1
+
+        isFound
+
+    /// Returns an int indicating the number of elements in the SmallSet
+    member _.Count = count
+
+    /// Retrieve an item by index from the SmallSet
+    member _.Item
+        with get k =
+            if k > count - 1 then
+                raise (IndexOutOfRangeException ())
+            else
+                values[k]
+
+    // A simple way to iterate through the values in the SmallSet.
+    member _.Values () =
+        seq { for i in 0 .. count -> values[i] }
 
 [<MemoryDiagnoser>]
 type Benchmarks () =
@@ -350,6 +432,7 @@ type Benchmarks () =
     let smallSetFastComparer = SmallSetFastComparer values
     let smallSetEqualityComparer = SmallSetEqualityComparer values
     let smallSetInt64 = SmallSetInt64 values
+    let smallSetGenericIEquatable = SmallSetGenericIEquatable values
 
     [<Benchmark>]
     member _.HashSetAdd () =
@@ -396,6 +479,15 @@ type Benchmarks () =
 
         result
 
+    [<Benchmark>]
+    member _.SmallSetGenericIEquatableAdd () =
+        let mutable result = false
+
+        for elem in addValues do
+            result <- smallSetGenericIEquatable.Add elem
+
+        result
+
     [<Benchmark>]
     member _.HashSetRemove () =
         let mutable result = false
@@ -441,6 +533,15 @@ type Benchmarks () =
 
         result
 
+    [<Benchmark>]
+    member _.SmallSetGenericIEquatableRemove () =
+        let mutable result = false
+
+        for elem in removeValues do
+            result <- smallSetGenericIEquatable.Remove elem
+
+        result
+
 
 
 let args = Environment.GetCommandLineArgs()[1..]