title: Relying on ADL for std::begin() and std::end()?
body: <p>When iterating over a standard container, do you think it's a good idea to omit the <code>std::</code> prefix and rely on ADL to find the definition? Example:</p>
  
  <pre><code>std::vector&lt;int&gt; vec = get_vec();
  // range-based for loop would be preferred here, but just for the sake of example
  for (auto it = begin(vec), end = end(vec); it != end; ++it) { /*...*/ }
  </code></pre>
  
  <p>Are there any reasons to do or not do this?</p>