Typst - Try to keep two things in the same page

stick-together.typ

// MIT No Attribution
// 
// Copyright (c) 2023 Pg Biel
// 
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// Attempts to ensure the two elements will be in the same page.
// The threshold specifies how early a pagebreak should be forced.
// That is, the minimum vertical space that both elements should
// have available in the same page; if they have less than that
// threshold, they are moved to the next page.
// A higher threshold means that a pagebreak is forced earlier.
// When using with tables, a threshold of at least the height
// of the heading + the header row + a little bit should be used
// to ensure the header rows won't be alone.
// E.g. 5em could be good for a small table, but you will have to fiddle
// with it (make sure to test it by pushing your table to the bottom and seeing
// how early the elements are moved to the next page).
#let stick-together(a, b, threshold: 3em) = {
  block(a + v(threshold), breakable: false)
  v(-1 * threshold)
  b
}

// --- EXAMPLE ---

#v(57.7em)  // increase the number to see how it skips to the next page

#stick-together(
  threshold: 5em,
  [= Hello world],
  // Table used as an example (works with other elements too)
  table(
    columns: 4,
    [*A*], [*B*], [E], [F],
    [A], [B], [C], [D],
    [A], [B], [C], [D],
    [A], [B], [C], [D],
    [A], [B], [C], [D],
    [A], [B], [C], [D],
    [A], [B], [C], [D],
    [A], [B], [C], [D],
    [A], [B], [C], [D],
    [A], [B], [C], [D],
  )
)