Macros
MathLive has over 800 LaTeX commands predefined. Some are primitives but others are macros, that is commands defined with a LaTeX expression.
To view the default macros, inspect the macros option:
import 'mathlive';
const mf = document.getElementById('mf');
console.log(mf.getOption('macros'));
<math-field id='mf'>x=\frac{-b\pm \sqrt{b^2-4ac}}{2a}</math-field>
To add or remove macros use setOptions({macros: ...}).
import 'mathlive';
const mf = document.getElementById('mf');
mf.setOptions({
macros: {
...mf.getOptions('macros'),
smallfrac: '{}^{#1}\\!\\!/\\!{}_{#2}',
}
});
<math-field id="mf">\scriptCapitalE=\smallfrac{5}{7}+\frac{5}{7}</math-field>
The macro definition can contain up to eight arguments, represented by #1 to #9.