title: PHP use statement for namespace
body: <p>Maybe this is weird question, but I can't work it out what happens internally in php when you write:</p>
  
  <pre><code>use garcha\path\class;
  </code></pre>
  
  <p>I'm not asking about purpose of namespaces, but about that statement itself, even it does not allocate any memory, I mean, when you even give an alias for some class:</p>
  
  <pre><code>use garcha\path\class as withNewName;
  </code></pre>
  
  <p>Where is it stored? Or how does it remember the names? Does it happen just on compile time? and not run time? something like just describing the function.</p>