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POHow to partition IEnumerable(Of T) based on pattern in order of T?
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copied!<p>Consider the following IEnumerable(Of String):</p> <pre><code> Moe1 Larry1 Curly1 Shemp1 Curly1 Moe2 Larry1 Curly1 Shemp1 Curly1 Curly2 Shemp2 Curly1 Curly2 Larry2 Curly1 Larry3 Shemp1 </code></pre> <p>They're visually split here to make the pattern easier to see. I want to partition an IEnumerable(Of String) using the .StartsWith() predicate, into an IEnumerable(Of IEnumerable(Of String).</p> <p>The rules are:</p> <ul> <li>every partitioned subset <em>must</em> have a <strong>Larry</strong>, and <em>might</em> have a Moe</li> <li>partition on <strong>Moe</strong> when <strong>Moe</strong> encountered</li> <li>if <strong>Larry</strong> immediately follows <strong>Moe</strong>, put him with the last <strong>Moe</strong></li> <li>if <strong>Larry</strong> immediately follows anyone else, partition on <strong>Larry</strong></li> <li>all other stooges are put with the current partition</li> <li>all stooges other than <strong>Moe</strong> and <strong>Larry</strong> can repeat in a partition</li> </ul> <p>I'm using the .StartsWith("Moe"), etc. to identify the type of stooge, but I'm having a hard time figuring out how to partition this set using LINQ operators so that <em>if</em> <strong>Moe</strong> is present, he represents the head of a partition, but since <strong>Larry</strong> must exist in each partition, he might represent the head of a partition if a <strong>Moe</strong> does not precede him.</p> <p>How can I create the IEnumerable(Of IEnumerable(Of String) so that the result is partitioned the way I display the set with blank lines?</p> <p>If there are no suitable LINQ operators for something like this (I'm programming in VB.NET if there are subtle differences in capabilities between VB.NET & C#), and I simply need to write a method to do this, I can do that, but I thought this might be a problem that comes up and is solved easily with LINQ operators.</p> <p>Thanks in advance.</p>

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