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BOBTFISH / Text-Markdown-1.000031 / t / docs-php-markdown-extra / Emphasis.html 
<p>Combined emphasis:</p>

<ol>
<li><strong><em>test test</em></strong></li>
<li><strong><em>test test</em></strong></li>
<li><em>test <strong>test</strong></em></li>
<li><strong>test <em>test</em></strong></li>
<li><strong><em>test</em> test</strong></li>
<li><em><strong>test</strong> test</em></li>
<li><strong><em>test</em> test</strong></li>
<li><strong>test <em>test</em></strong></li>
<li><em>test <strong>test</strong></em></li>
<li><em>test <strong>test</strong></em></li>
<li><strong>test <em>test</em></strong></li>
<li><strong><em>test</em> test</strong></li>
<li><em><strong>test</strong> test</em></li>
<li><strong><em>test</em> test</strong></li>
<li><strong>test <em>test</em></strong></li>
<li><em>test <strong>test</strong></em></li>
</ol>

<p>Incorrect nesting:</p>

<ol>
<li>*test  <strong>test*  test</strong></li>
<li>_test  <strong>test_  test</strong></li>
<li>**test  <em>test</em>* test*</li>
<li>__test  <em>test</em>_ test_</li>
<li><em>test   *test</em>  test*</li>
<li><em>test   _test</em>  test_</li>
<li><strong>test <strong>test</strong> test</strong></li>
<li><strong>test <strong>test</strong> test</strong></li>
</ol>

<p>No emphasis:</p>

<ol>
<li>test*  test  *test</li>
<li>test** test **test</li>
<li>test_  test  _test</li>
<li>test__ test __test</li>
</ol>

<p>Middle-word emphasis (asterisks):</p>

<ol>
<li><em>a</em>b</li>
<li>a<em>b</em></li>
<li>a<em>b</em>c</li>
<li><strong>a</strong>b</li>
<li>a<strong>b</strong></li>
<li>a<strong>b</strong>c</li>
</ol>

<p>Middle-word emphasis (underscore):</p>

<ol>
<li>_a_b</li>
<li>a_b_</li>
<li>a_b_c</li>
<li>__a__b</li>
<li>a__b__</li>
<li>a__b__c</li>
</ol>

<p>my_precious_file.txt</p>

<h2>Tricky Cases</h2>

<p>E**. <strong>Test</strong> TestTestTest</p>

<p>E**. <strong>Test</strong> Test Test Test</p>