<!DOCTYPE html>
<html>
  <head>
    <title>embellished operators 5: vertical stretchy operator</title>
  </head>

  <body>
    <div>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
        <mrow>
          <mrow>
            <msub>
              <mo>|</mo>
              <mspace/>
            </msub>
          </mrow>
          <mspace height="30px" depth="30px"/>
        </mrow>
      </math>
    </div>
  </body>
</html>