netcore/System.Private.CoreLib/shared/System/ByReference.cs

   1 // Licensed to the .NET Foundation under one or more agreements.
   2 // The .NET Foundation licenses this file to you under the MIT license.
   3 // See the LICENSE file in the project root for more information.
   4
   5 using System.Runtime.CompilerServices;
   6 using System.Runtime.Versioning;
   7
   8 namespace System
   9 {
  10     // ByReference<T> is meant to be used to represent "ref T" fields. It is working
  11     // around lack of first class support for byref fields in C# and IL. The JIT and
  12     // type loader has special handling for it that turns it into a thin wrapper around ref T.
  13     [NonVersionable]
  14     internal readonly ref struct ByReference<T>
  15     {
  16         // CS0169: The private field '{blah}' is never used
  17 #pragma warning disable 169
  18 #pragma warning disable CA1823
  19         private readonly IntPtr _value;
  20 #pragma warning restore CA1823
  21 #pragma warning restore 169
  22
  23         [Intrinsic]
  24         public ByReference(ref T value)
  25         {
  26             // Implemented as a JIT intrinsic - This default implementation is for
  27             // completeness and to provide a concrete error if called via reflection
  28             // or if intrinsic is missed.
  29             throw new PlatformNotSupportedException();
  30         }
  31
  32         public ref T Value
  33         {
  34             [Intrinsic]
  35             get
  36             {
  37                 // Implemented as a JIT intrinsic - This default implementation is for
  38                 // completeness and to provide a concrete error if called via reflection
  39                 // or if the intrinsic is missed.
  40                 throw new PlatformNotSupportedException();
  41             }
  42         }
  43     }
  44 }