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copied!<p>For a little more comprehensive solution, you could check out the <a href="http://Refactoring.Com/catalog/introduceNullObject.html" rel="nofollow noreferrer"><em>Introduce Null Object</em> Refactoring</a>. The basic mechanics of this refactoring is that instead of checking for <code>nil</code> in the <em>client</em> code you instead make sure that the <em>provider</em> never produces a <code>nil</code> in the first place, by introducing a context-specific <em>null object</em> and returning that.</p> <p>So, return an empty string, an empty array, an empty hash or a special empty customer or empty user or something instead of just <code>nil</code> and then you will never need to check for <code>nil</code> in the first place.</p> <p>So, in your case you would have something like</p> <pre><code>class NullUser < User def name return '' end end </code></pre> <p>However, in Ruby there is actually another, quite elegant, way of implementing the Introduce Null Object Refactoring: you don't actually need to <em>introduce</em> a Null Object, because <code>nil</code> is <em>already</em> an object! So, you could monkey-patch <code>nil</code> to behave as a NullUser – however, all the usual warnings and pitfalls regarding monkey-patching apply even more strongly in this case, since making <code>nil</code> silently swallow <code>NoMethodError</code>s or something like that can totally mess up your debugging experience and make it <em>really</em> hard to track down cases where there is a <code>nil</code> that shouldn't be there (as opposed to a <code>nil</code> that serves as a Null Object).</p>

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