title: This expression was expected to have type xxxx but here has type unit
body: <p>The following code has a type error for both of the <code>printfn</code>s.</p>
  
  <p>How should I fix it? I'd like the <code>Seq.map</code> loop to continue even if one of the items fails.</p>
  
  <pre><code>// files should be a Seq of record 
  let files = seqOfStrs |&gt; Seq.map(fun s -&gt;
      match s with
      | Helper.ParseRegex "(\w+) xxxxx" month -&gt;
          let currentMonth =  .....
          if currentMonth = month.[0] then
              doc.Load(shelf)
              // parse doc and return record type. Omitted
          else
              printfn "Expect %s found %s." currentMonth month.[0] //Error
      | _ -&gt;
          printfn "No '(Month) Payment Data On Line' prompt." //Error
  </code></pre>