title: Eclipse PDT does not propose all php functions
body: <p>Eclipse PDT Neon doesn't offer all of PHP functions. for example if i type "is", it just offering me isset:</p>
  
  <p><a href="https://i.stack.imgur.com/AmHyH.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/AmHyH.png" alt="Eclipse PDT PHP default proposals"></a></p>
  
  <p>This my .buildpath:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="UTF-8"?&gt;
  &lt;buildpath&gt;
      &lt;buildpathentry kind="src" path=""/&gt;
      &lt;buildpathentry kind="con" path="org.eclipse.php.core.LANGUAGE"/&gt;
  &lt;/buildpath&gt;
  </code></pre>
  
  <p>Also these are my .project natures:</p>
  
  <pre><code>&lt;nature&gt;org.eclipse.php.core.PHPNature&lt;/nature&gt;
  &lt;nature&gt;org.eclipse.wst.jsdt.core.jsNature&lt;/nature&gt;
  &lt;nature&gt;org.eclipse.wst.common.project.facet.core.nature&lt;/nature&gt;
  </code></pre>
  
  <p>I removed Eclipse folder and default workspace folder inside /home/{user}/workspace and download Eclipse PDT Neon again, but it didn't help.</p>
  
  <p>I did removed all projects from Eclipse, Removed all of Eclipse files from my project folder (like .project, .buildpath, ...) and then add projects to the eclipse again but it didn't help.</p>
  
  <p>I must add all of my projects configured to PHP7 Interpreter and this is my PHP code assist settings:</p>
  
  <p><a href="https://i.stack.imgur.com/8xrm9.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/8xrm9.png" alt="Eclipse Code Assist"></a></p>