implab/ImplabNet Files · Implab/src/Components/LazyAndWeak.cs

Fixed promise rejection when there is not specified error handler in the reaction....

Fixed promise rejection when there is not specified error handler in the reaction. FIXED SPELLING IN THE XML CONTAINER CONFIGURATION signleton->singleton Code cleanup Update tests make them working on dotnet core

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             LazyAndWeak.cs
        
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             / Implab / src / Components / LazyAndWeak.cs
          
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      using System;

      using System.Threading;

      namespace Implab.Components {

          /// <summary>

          /// Creates an instace on-demand and allows it to be garbage collected.

          /// </summary>

          /// <remarks>

          /// Usefull when dealing with memory-intensive objects which are frequently used.

          /// This class is similar to <see cref="ObjectPool{T}"/> except it is a singleton.

          /// This class can't be used to hold diposable objects.

          /// </remarks>

          public class LazyAndWeak<T> where T : class {

              readonly Func<T> m_factory;

              readonly object m_lock;

              WeakReference m_reference;

              public LazyAndWeak(Func<T> factory, bool useLock) {

                  Safe.ArgumentNotNull(factory, "factory");

                  m_factory = factory;

                  m_lock = useLock ? new object() : null;

              }

              public LazyAndWeak(Func<T> factory) : this(factory, false) {

              }

              public T Value {

                  get {

                      while (true) {

                          var weak = m_reference;

                          T value;

                          if (weak != null) {

                              value = weak.Target as T;

                              if (value != null)

                                  return value;

                          }

                          if (m_lock == null) {

                              value = m_factory();

                              if (Interlocked.CompareExchange(ref m_reference, new WeakReference(value), weak) == weak)

                                  return value;

                          } else {

                              lock (m_lock) {

                                  // double check

                                  weak = m_reference;

                                  if (weak != null) {

                                      value = weak.Target as T;

                                      if (value != null)

                                          return value;

                                  }

                                  // we are safe to write

                                  value = m_factory();

                                  m_reference = new WeakReference(value);

                                  return value;

                              }

                          }

                      }

                  }

              }

          }

      }

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				using System;
				using System.Threading;

				namespace Implab.Components {
				/// <summary>
				/// Creates an instace on-demand and allows it to be garbage collected.
				/// </summary>
				/// <remarks>
				/// Usefull when dealing with memory-intensive objects which are frequently used.
				/// This class is similar to <see cref="ObjectPool{T}"/> except it is a singleton.
				/// This class can't be used to hold diposable objects.
				/// </remarks>
				public class LazyAndWeak<T> where T : class {

				readonly Func<T> m_factory;
				readonly object m_lock;
				WeakReference m_reference;


				public LazyAndWeak(Func<T> factory, bool useLock) {
				Safe.ArgumentNotNull(factory, "factory");
				m_factory = factory;
				m_lock = useLock ? new object() : null;
				}

				public LazyAndWeak(Func<T> factory) : this(factory, false) {
				}

				public T Value {
				get {
				while (true) {
				var weak = m_reference;
				T value;
				if (weak != null) {
				value = weak.Target as T;
				if (value != null)
				return value;
				}

				if (m_lock == null) {
				value = m_factory();

				if (Interlocked.CompareExchange(ref m_reference, new WeakReference(value), weak) == weak)
				return value;
				} else {
				lock (m_lock) {
				// double check
				weak = m_reference;
				if (weak != null) {
				value = weak.Target as T;
				if (value != null)
				return value;
				}
				// we are safe to write
				value = m_factory();
				m_reference = new WeakReference(value);
				return value;
				}
				}
				}
				}
				}
				}
				}