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copied!<p>To add a bit of extra information on how I solved this problem I thought it'd be useful to post an associative answer.</p> <p>The "standard" way of chaining method calls is to return an instance of the same class upon which subsiquent method calls can be made.</p> <p>My original code did this by directly returning <code>this</code>, however, since my methods were mutating fields by building up collections of <code>Func<T></code>'s, this left the consumer open to threading and reentry issues.</p> <p>To solve this problem I decided to impliment <code>ICloneable</code> and have it return a new instance of the same class via <code>object.MemberwiseClone()</code>. This shallow-clone works fine my this case because the fields being added to were value types which are copied over during the shallw-clone process.</p> <p>Each public method in my class now executes the instances <code>Clone</code> method and updates the private fields before returning the clone such that:</p> <pre><code>public class ServiceManager : IServiceManager { /// <summary> /// A collection of Funcs to execute if the service fails. /// </summary> private readonly List<Func<dynamic>> failedFuncs = new List<Func<dynamic>>(); /// <summary> /// The number of times the service call has been attempted. /// </summary> private int count; /// <summary> /// The number of times to re-try the service if it fails. /// </summary> private int attemptsAllowed; /// <summary> /// Gets or sets a value indicating whether failed. /// </summary> public bool Failed { get; set; } /// <summary> /// Gets or sets the service func. /// </summary> private Func<dynamic> ServiceFunc { get; set; } /// <summary> /// Gets or sets the result implimentation. /// </summary> private dynamic ResultImplimentation { get; set; } /// <summary> /// Gets the results. /// </summary> /// <typeparam name="TResult"> /// The result. /// </typeparam> /// <returns> /// The TResult. /// </returns> public TResult Result<TResult>() { var result = this.Execute<TResult>(); return result; } /// <summary> /// The execute service. /// </summary> /// <typeparam name="TResult"> /// The result. /// </typeparam> /// <param name="action"> /// The action. /// </param> /// <param name="attempts"> /// The attempts. /// </param> /// <returns> /// ServiceManager.IServiceManager. /// </returns> public IServiceManager ExecuteService<TResult>( Func<TResult> action, int attempts) { var serviceManager = (ServiceManager)this.Clone(); serviceManager.ServiceFunc = (dynamic)action; serviceManager.attemptsAllowed = attempts; return serviceManager; } /// <summary> /// The if service fails. /// </summary> /// <typeparam name="TResult"> /// The result. /// </typeparam> /// <param name="action"> /// The action. /// </param> /// <returns> /// ServiceManager.IServiceManager`1[TResult -&gt; TResult]. /// </returns> public IServiceManager IfServiceFailsThen<TResult>( Func<TResult> action) { var serviceManager = (ServiceManager)this.Clone(); serviceManager.failedFuncs.Add((dynamic)action); return serviceManager; } /// <summary> /// Clones the current instance of ServiceManager. /// </summary> /// <returns> /// An object reprisenting a clone of the current ServiceManager. /// </returns> public object Clone() { return this.MemberwiseClone(); } } </code></pre> <p>Private methods removed for brevity. Full source code can be found here:</p> <p><a href="https://github.com/JamieDixon/ServiceManager" rel="nofollow">https://github.com/JamieDixon/ServiceManager</a></p>

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