title: pivot_longer into multiple columns
body: <p>I am trying to use <code>pivot_longer</code>. However, I am not sure how to use <code>names_sep</code> or <code>names_pattern</code> to solve this.</p>
  <pre><code>dat &lt;- tribble(
       ~group,  ~BP,  ~HS,  ~BB, ~lowerBP, ~upperBP, ~lowerHS, ~upperHS, ~lowerBB, ~upperBB,
          &quot;1&quot;, 0.51, 0.15, 0.05,     0.16,     0.18,      0.5,     0.52,     0.14,     0.16,
        &quot;2.1&quot;, 0.67, 0.09, 0.06,     0.09,     0.11,     0.66,     0.68,     0.08,      0.1,
        &quot;2.2&quot;, 0.36, 0.13, 0.07,     0.12,     0.15,     0.34,     0.38,     0.12,     0.14,
        &quot;2.3&quot;, 0.09, 0.17, 0.09,     0.13,     0.16,     0.08,     0.11,     0.15,     0.18,
        &quot;2.4&quot;, 0.68, 0.12, 0.07,     0.12,     0.14,     0.66,     0.69,     0.11,     0.13,
          &quot;3&quot;, 0.53, 0.15, 0.06,     0.14,     0.16,     0.52,     0.53,     0.15,     0.16)
                 
  </code></pre>
  <p>Desired output (First row from wide data)</p>
  <pre><code>group names   values lower upper
     1    BP      0.51  0.16  0.18
     1    HS      0.15  0.5   0.52
     1    BB      0.05  0.14  0.16
  </code></pre>