Infix \vert produces wrong math output

[dginev]

I have distilled a minimal example from the arxiv-vanity 1603.00788, which (besides some missing package issues, notably glossaries.sty) has some broken equations.

The core problem comes from a redefinition of \mid as:

\documentclass{article}

\usepackage{amsmath}
\DeclareRobustCommand{\mb}[1]{\mathbf{\boldsymbol{#1}}}
\renewcommand{\mid}{~\vert~}
\newcommand{\mbx}{\mb{x}}
\newcommand{\mbtheta}{\mb{\theta}}

\begin{document}

$p (\mbx\mid\mbtheta)$

\end{document}

The problems are two-fold:

• First, firefox renders the MathML with the vertical bar as prefix, as opposed to the regular probability syntax in the PDF:

  • Firefox:

  • PDF:

  • I haven't checked the mathjax rendering, but there comes part 2 of the issue.

• Second, the tex attribute is very low-level and out of scope for renderers like MathJax, because of commands such as \leavevmode and \nobreak. This may not be latexml's problem to solve, and could indeed be better addressed by solving #432 , which suggests adding a "high-level macro" math annotation attribute. My minimal example produces a slightly different string, but on arxiv-vanity it is:

  p(\mathbf{\boldsymbol{x}}\leavevmode\nobreak\ |\leavevmode\nobreak\ \mathbf{%
  \boldsymbol{\theta}})

[dginev]

I should also attach the presentation MathML that I made a FF screenshot for:

<mrow>
   <mi>p</mi>
   <mo>⁢</mo>
   <mrow>
      <mo stretchy="false">(</mo>
      <mrow>
         <mo rspace="5.8pt" stretchy="false">|</mo>
         <mo>⁡</mo>
         <mpadded width="+3.3pt">
            <mi>&#x1d431;</mi>
         </mpadded>
         <mi>&#x1d73d;</mi>
      </mrow>
      <mo stretchy="false">)</mo>
   </mrow>
</mrow>

[brucemiller]

Ah, simple problem; when I tweaked the grammar to recognize various forms of VERTBAR as infix, I forgot to update the grammatical role so postprocessing would treat it as infix. Fixed now! Thanks for the report.