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//
// System.Nullable.cs
//
// Martin Baulig (martin@ximian.com)
// Marek Safar (marek.safar@gmail.com)
//
// (C) 2004 Novell, Inc.
//
//
// Copyright (C) 2004 Novell, Inc (http://www.novell.com)
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
//
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
using System.Reflection;
using System.Collections.Generic;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Diagnostics;
namespace System
{
public partial struct Nullable<T> where T: struct
{
//
// These are called by the JIT
//
#pragma warning disable 169
//
// JIT implementation of box valuetype System.Nullable`1<T>
//
static object Box (T? o)
{
if (!o.hasValue)
return null;
return o.value;
}
static T? Unbox (object o)
{
if (o == null)
return null;
return (T) o;
}
static T? UnboxExact (object o)
{
if (o == null)
return null;
if (o.GetType() != typeof (T))
throw new InvalidCastException();
return (T) o;
}
#pragma warning restore 169
}
}
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