// returns minimal time needed
static long benchFor10(S desc default str(r), Runnable r) {
  ret benchForNSeconds(desc, r, 10);
}

// returns result of function
static <A> A benchFor10(S desc default str(f), IF0<A> f) {
  benchFor10(r { f! });
  ret f!;
}

Began life as a copy of #1018495