title: How to use fold method of StringOps in Scala?
body: <p>I tried to calculate the product of the unicode of the String "Hello" in scala. And in the StringOps scala API, I found the method fold and foldLeft and I wrote some code by using the above 2 methods:</p>
  
  <pre><code>val s = "Hello"
  s.fold(1L){(z, i) =&gt; z*i}
  s.foldLeft(1L){(z, i) =&gt; z*i}
  </code></pre>
  
  <p>By using the 2nd expression, I can get the correct answer, but the first cannot and the IDE complains "cannot resolve symbol *", anybody can explain this? </p>