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copied!<p>I understand it's <code>MoveNext</code> that throws the exception. </p> <p>I tried to write a method that safe-walks a sequence and tries to ignore <code>MoveNext</code> exceptions. However I'm not sure if <code>MoveNext</code> advances position when it throws an exception, so this might as well be infinite loop. It is also bad idea because we would rely on implementation details.</p> <p>But it's just <strong>so much fun!</strong></p> <pre><code>public static IEnumerable<T> SafeWalk<T> (this IEnumerable<T> source) { var enumerator = source.GetEnumerator(); bool? hasCurrent = null; do { try { hasCurrent = enumerator.MoveNext(); } catch { hasCurrent = null; // we're not sure } if (hasCurrent ?? false) // if not sure, do not return value yield return enumerator.Current; } while (hasCurrent ?? true); // if not sure, continue walking } foreach (var file in Directory.EnumerateFiles("c:\\", "*", SearchOption.AllDirectories) .SafeWalk()) { // ... } </code></pre> <p>This will only work if the following conditions are true about framework's implementation of this iterator (see <code>FileSystemEnumerableIterator<TSource></code> in Reflector for reference):</p> <ul> <li><code>MoveNext</code> advances its position when it fails;</li> <li>When <code>MoveNext</code> fails on last element, subsequent calls will return <code>false</code> instead of throwing an exception;</li> <li>This behavior is consistent for different versions of .NET Framework;</li> <li>I haven't made any logic or syntax mistakes.</li> </ul> <p>Even if it works, please, never use it in production!<br> But I really wonder if it does.</p>

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