Fishery

2022-10-24 18:56:18 +02:00
parent 01ef055ff2
commit 9cdc8ccb4f
70 changed files with 19754 additions and 4 deletions
@@ -0,0 +1,55 @@
+// Copyright (c) 2022 bradson
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+using System.Diagnostics.CodeAnalysis;
+using System.Runtime.CompilerServices;
+
+namespace FisheryLib;
+public static class HashCode
+{
+	[MethodImpl(MethodImplOptions.AggressiveInlining)]
+	public static unsafe int Get<T>([AllowNull] T obj)
+		=> FunctionPointers.GetHashCode<T>.Default(obj!);
+
+	[MethodImpl(MethodImplOptions.AggressiveInlining)]
+	public static unsafe int Get<T>([AllowNull] ref T obj)
+		=> FunctionPointers.GetHashCodeByRef<T>.Default(ref obj!);
+
+	[MethodImpl(MethodImplOptions.AggressiveInlining)]
+	public static int Combine<T_first, T_second>(T_first first, T_second second)
+		//where T_first : notnull where T_second : notnull
+		=> Combine(Get(first), Get(second));
+
+	[MethodImpl(MethodImplOptions.AggressiveInlining)]
+	public static int Combine(int first, int second)
+		=> unchecked((1009 * 9176) + first).CombineWith(second); //https://stackoverflow.com/questions/1646807/quick-and-simple-hash-code-combinations/34006336#34006336
+
+	[MethodImpl(MethodImplOptions.AggressiveInlining)]
+	public static int Combine<T_first, T_second, T_third>(T_first first, T_second second, T_third third)
+		//where T_first : notnull where T_second : notnull where T_third : notnull
+		=> Combine(first, second).CombineWith(third);
+
+	[MethodImpl(MethodImplOptions.AggressiveInlining)]
+	public static int Combine(int first, int second, int third)
+		=> Combine(first, second).CombineWith(third);
+
+	[MethodImpl(MethodImplOptions.AggressiveInlining)]
+	public static int Combine<T_first, T_second, T_third, T_fourth>(T_first first, T_second second, T_third third, T_fourth fourth)
+		//where T_first : notnull where T_second : notnull where T_third : notnull where T_fourth : notnull
+		=> Combine(first, second, third).CombineWith(fourth);
+
+	[MethodImpl(MethodImplOptions.AggressiveInlining)]
+	public static int Combine(int first, int second, int third, int fourth)
+		=> Combine(first, second, third).CombineWith(fourth);
+
+	[MethodImpl(MethodImplOptions.AggressiveInlining)]
+	private static int CombineWith(this int first, int second)
+		=> unchecked((first * 9176) + second);
+
+	[MethodImpl(MethodImplOptions.AggressiveInlining)]
+	private static int CombineWith<T>(this int first, T second)
+		//where T : notnull
+		=> unchecked((first * 9176) + Get(second));
+}