// Test under/over things.

--- math-underover-brace ---
// Test braces.
$ x = underbrace(
  1 + 2 + ... + 5,
  underbrace("numbers", x + y)
) $

--- math-underover-line-bracket ---
// Test lines and brackets.
$ x = overbracket(
  overline(underline(x + y)),
  1 + 2 + ... + 5,
) $

--- math-underover-brackets ---
// Test brackets.
$ underbracket([1, 2/3], "relevant stuff")
          arrow.l.r.double.long
  overbracket([4/5,6], "irrelevant stuff") $

--- math-underover-parens ---
// Test parentheses.
$ overparen(
  underparen(x + y, "long comment"),
  1 + 2 + ... + 5  
) $

--- math-underover-shells ---
// Test tortoise shell brackets.
$ undershell(
  1 + overshell(2 + ..., x + y),
  "all stuff"
) $