Fixed extension receiver type

Author: sakno

src/DotNext.Tests/Buffers/UnmanagedMemoryPoolTests.cs

@@ -242,7 +242,7 @@ public static unsafe void Pinning()
     public static unsafe void MarshalAsMemory()
     {
         var ptr = stackalloc int[] { 10, 20, 30 };
-        var memory = Memory<int>.FromPointer(ptr, 3);
+        var memory = MemoryMarshal.AsMemory(ptr, 3);
         False(memory.IsEmpty);
         Equal([10, 20, 30], memory.Span);
 

src/DotNext.Unsafe/Buffers/UnmanagedMemory.cs

@@ -64,7 +64,7 @@ private static UnmanagedMemoryOwner<T, TAllocator> Allocate<TAllocator>(int leng
         public static MemoryAllocator<T> Unmanaged => GetAllocator<T>(zeroMem: false);
 
         /// <summary>
-        /// Gets the unmanaged memoir
+        /// Gets the unmanaged memory allocator that can be used to obtain a block of unmanaged memory filled with zeroes.
         /// </summary>
         public static MemoryAllocator<T> UnmanagedZeroMem => GetAllocator<T>(zeroMem: true);
 
@@ -83,17 +83,18 @@ static MemoryOwner<T> Allocate<TAllocator>(int length)
     /// <summary>
     /// Extends <see cref="Memory{T}"/> type.
     /// </summary>
-    /// <typeparam name="T">The type of elements in the memory.</typeparam>
-    extension<T>(Memory<T>) where T : unmanaged
+    extension(MemoryMarshal)
     {
         /// <summary>
         /// Wraps unmanaged pointer to <see cref="Memory{T}"/>.
         /// </summary>
+        /// <typeparam name="T">The type of elements in the memory.</typeparam>
         /// <param name="pointer">The pointer to a sequence of elements.</param>
         /// <param name="length">The number of elements.</param>
         /// <returns>The memory block that represents the data located at the pointer.</returns>
         [CLSCompliant(false)]
-        public static unsafe Memory<T> FromPointer(T* pointer, int length)
+        public static unsafe Memory<T> AsMemory<T>(T* pointer, int length)
+            where T : unmanaged
         {
             ArgumentNullException.ThrowIfNull(pointer);
             ArgumentOutOfRangeException.ThrowIfNegative(length);

src/DotNext.Unsafe/IO/PointerExtensions.cs

@@ -1,3 +1,5 @@
+using System.Runtime.InteropServices;
+
 namespace DotNext.IO;
 
 using Buffers;
@@ -170,7 +172,7 @@ private static async ValueTask WriteToAsync(Pointer<byte> source, long length, S
             Memory<byte> memory;
             unsafe
             {
-                memory = Memory<byte>.FromPointer(source, count);
+                memory = MemoryMarshal.AsMemory<byte>(source, count);
             }
 
             await destination.WriteAsync(memory, token).ConfigureAwait(false);
@@ -197,7 +199,7 @@ private static async ValueTask<long> ReadFromStreamAsync(Stream source, Pointer<
             Memory<byte> memory;
             unsafe
             {
-                memory = Memory<byte>.FromPointer(destination, int.CreateSaturating(length));
+                memory = MemoryMarshal.AsMemory<byte>(destination, int.CreateSaturating(length));
             }
 
             if ((bytesRead = await source.ReadAsync(memory, token).ConfigureAwait(false)) is 0)