title: What does the slash notation in Elixir mean?
body: <p>In the Elixir docs, they keep using an odd notation with slash, for example:</p>
  
  <pre><code>is_boolean/1
  IO.puts/1
  String.length/1
  is_function/2
  ++/2
  </code></pre>
  
  <p>I'm just guessing, but I think it refers to arity. But if that's the case, why the devil isn't it mentioned anywhere in the docs? It's not as if this is any kind of standard convention in IT (at least, not one that I've ever seen in my 20+ years in IT).</p>