MathML msqrt not supported

[Omikhleia]

SILE 0.14.4

Document:

<document>
<use module="packages.math"/>

<mathml display="block"><mfrac><mrow><mo>−</mo><mi>b</mi><mo>±</mo><msqrt><mrow><mi mathvariant="normal">Δ</mi></mrow></msqrt></mrow><mrow><mn>2</mn><mi>a</mi></mrow></mfrac></mathml>

</document>

(I am not MathML-savvy, the MathML formula was generated with TEMML from LaTeX \frac{-b + \sqrt {\Delta}}{2a})

Expected:

Observed:

! Unknown math command msqrt at xmath.xml:50:1: in \mathml["display",display="block"]

[Omikhleia]

Actually, switching to the TeX-like math does produce some result:

\begin{document}
\use[module=packages.math]

\begin{math}
\frac{-b + \sqrt {\Delta}}{2a}
\end{math}

\end{document}

But the square root doesn't expand over the content.

(FWIW, my math font is Libertinus Math)

[alerque]

@OlivierNicole No pressure to fix this, I'll totally understand if you don't have the bandwidth. But perhaps you could at least drop a pointer for what somebody needs to look into if they want to tackle this.

[OlivierNicole]

Indeed, square roots are not yet implemented. What you see when doing \sqrt in TeX-like mode is just the Unicode glyph for square roots.

Typesetting square roots is not entirely trivial because it’s a vertically stretchable glyph (see #220 (comment)). No theoretical difficulties there, just implementation time

Alas I cannot commit on starting working on this seriously anytime soon.

[Omikhleia]

The above XML MathML test script with PR #2119: