Neutral Bracketing issues

[zorkow]

Somewhat expected behaviour. But the example exposes a number of other issues:

• Bracketing algorithm is greedy from the left. The evaluation bar is therefore taken to be the neutral fence. You either get the left hand side correct or the right hand side.
• Converting the left-over bar to punctuation breaks up the relation. The heuristic to convert to pre-/postfix operators (part of the bra-ket heuristic) should help.
• The metric bars should probably not be spoken as parallel.

Originally posted by @zorkow in #462 (comment)

[zorkow]

\begin{equation} \bigg |\Big (\frac {\partial }{\partial r}\Big )^{\beta }\Big \langle { \frac {\partial ^{\alpha }\hat{f}}{\partial \xi _d^{\alpha }}\psi },{ \frac {\partial ^{\alpha }\hat{g}}{\partial \xi _d^{\alpha }}\psi }\Big \rangle _{\dot{H}^{-\gamma }(\Sigma _r)}\bigg |_{r=0}\bigg | \lesssim \|f\|_{L_p}\|g\|_{L_p}. \tag{49} \end{equation}

[zorkow]

Example taken from issue #314

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    <mrow class="MJX-TeXAtom-ORD">
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    </mrow>
    <mi>A</mi>
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    <msup>
      <mrow class="MJX-TeXAtom-ORD">
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      <mn>2</mn>
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</math>