title: regex may or maynot contain a character
body: <p>I have some regex I am using in PHP:</p>
  
  <pre><code>preg_match_all('/D3m57D3m58(.+)D3m59/Uis', $content, $m)
  </code></pre>
  
  <p>This works fine for most of the stuff, but in some examples  <code>D3m57</code> and <code>D3m58</code> may be separated by a new line, thus no match.</p>
  
  <p>How can I get this to match even if there is a new line in between them, but it still match even if there is not...</p>
  
  <p>i cant alter the string it is matching against</p>