code.grnet.gr Git - pithos-ms-client/blob - trunk/Libraries/ParallelExtensionsExtras/Extensions/LazyExtensions.cs

   1 //--------------------------------------------------------------------------
   2 //
   3 //  Copyright (c) Microsoft Corporation.  All rights reserved.
   4 //
   5 //  File: LazyExtensions.cs
   6 //
   7 //--------------------------------------------------------------------------
   8
   9 using System.Threading;
  10 using System.Threading.Tasks;
  11
  12 namespace System
  13 {
  14     /// <summary>Extension methods for Lazy.</summary>
  15     public static class LazyExtensions
  16     {
  17         /// <summary>Forces value creation of a Lazy instance.</summary>
  18         /// <typeparam name="T">Specifies the type of the value being lazily initialized.</typeparam>
  19         /// <param name="lazy">The Lazy instance.</param>
  20         /// <returns>The initialized Lazy instance.</returns>
  21         public static Lazy<T> Force<T>(this Lazy<T> lazy)
  22         {
  23             var ignored = lazy.Value;
  24             return lazy;
  25         }
  26
  27         /// <summary>Retrieves the value of a Lazy asynchronously.</summary>
  28         /// <typeparam name="T">Specifies the type of the value being lazily initialized.</typeparam>
  29         /// <param name="lazy">The Lazy instance.</param>
  30         /// <returns>A Task representing the Lazy's value.</returns>
  31         public static Task<T> GetValueAsync<T>(this Lazy<T> lazy)
  32         {
  33             return Task.Factory.StartNew(() => lazy.Value);
  34         }
  35
  36         /// <summary>Creates a Lazy that's already been initialized to a specified value.</summary>
  37         /// <typeparam name="T">The type of the data to be initialized.</typeparam>
  38         /// <param name="value">The value with which to initialize the Lazy instance.</param>
  39         /// <returns>The initialized Lazy.</returns>
  40         public static Lazy<T> Create<T>(T value)
  41         {
  42             return new Lazy<T>(() => value, false).Force();
  43         }
  44     }
  45 }