How to check it is math.display?

Questions
1 
#show math.equation.where(block: false): it => {
  return it.body.func() == math.display
}
$0$, $display(a / b)$.
1 Like
2

Since math.display is not an element, you can’t make a transparent wrapper or search for it.

I don’t know why you need this, but here it is:

#let display(..args) = metadata("is-display") + math.display(..args)
#show math.equation.where(block: false): it => {
  if (
    it.body.func() != [].func()
      or it.body.children.first().func() != metadata
      or it.body.children.first().value != "is-display"
  ) { return false }
  true
}
$0$, $display(a / b)$.

image

#let is-display = state("is-display", false)
#let display(..args) = {
  is-display.update(true)
  math.display(..args)
  is-display.update(false)
}
#show math.frac: it => context is-display.get()
$0$, $a / b$, $display(a / b)$.

image