title: Elm: How does Debug.log work?
body: <p>I'm logging the <code>a</code> and <code>b</code> values of a <code>foldl</code>.</p>
  
  <pre><code>words = ["mate", "bro", "bruv"]
  
  sum2 = List.foldl
      (\a b -&gt;
          Debug.log(toString &lt;| a)
          Debug.log(toString &lt;| b)
          a
      ) "guv" words
  </code></pre>
  
  <p>It works as expected, but I can't understand the output:</p>
  
  <pre><code>"mate": &lt;function&gt;
  "guv": "mate"
  "bro": &lt;function&gt;
  "mate": "bro"
  "bruv": &lt;function&gt;
  "bro": "bruv"
  </code></pre>
  
  <p>Why is it outputting <code>a</code> as a <code>&lt;function&gt;</code>, and what is it outputting <code>b</code> as <code>a:b</code> ?</p>