msubsup-05.test

<<< mml
<?xml version="1.0" encoding="UTF-8"?>

<math xmlns="http://www.w3.org/1998/Math/MathML" display="block">  <msubsup>    <mi>S</mi>     <mrow>      <msubsup>        <mi>Q</mi>         <mn>4</mn>         <mn>3</mn>       </msubsup>     </mrow>     <mrow>      <msubsup>        <mi>P</mi>         <mn>2</mn>         <mn>1</mn>       </msubsup>     </mrow>   </msubsup>   <mo>=</mo>   <msubsup>    <mi>S</mi>     <mrow>      <msubsup>        <mi>Q</mi>         <mrow>          <mn>4</mn>
          <mphantom>
            <mtext>z</mtext>
          </mphantom>
        </mrow>         <mn>3</mn>       </msubsup>     </mrow>     <mrow>      <msubsup>        <mi>P</mi>         <mn>2</mn>         <mrow>          <mn>1</mn>
          <mphantom>
            <mtext>z</mtext>
          </mphantom>
        </mrow>       </msubsup>     </mrow>   </msubsup> </math>
>>> native
[ ESubsup
    (EIdentifier "S")
    (ESubsup (EIdentifier "Q") (ENumber "4") (ENumber "3"))
    (ESubsup (EIdentifier "P") (ENumber "2") (ENumber "1"))
, ESymbol Rel "="
, ESubsup
    (EIdentifier "S")
    (ESubsup
       (EIdentifier "Q")
       (EGrouped [ ENumber "4" , EPhantom (EText TextNormal "z") ])
       (ENumber "3"))
    (ESubsup
       (EIdentifier "P")
       (ENumber "2")
       (EGrouped [ ENumber "1" , EPhantom (EText TextNormal "z") ]))
]