subroutineappendprivate

subroutine append(c, node)
    type(fypp_t), intent(inout) :: c    !! the state
    integer, intent(in) :: node         !! the node
    integer, allocatable :: grown(:)
    integer :: parent, body, n

    parent = c%root
    if (c%depth > 0) parent = c%stack(c%depth)
    body = size(c%nodes(parent)%block%bodies)
    associate (b => c%nodes(parent)%block%bodies(body))
        n = b%n
        if (n == size(b%ids)) then
            allocate (grown(2*n))
            grown(1:n) = b%ids(1:n)
            call move_alloc(grown, b%ids)
        end if
        b%ids(n + 1) = node
        b%n = n + 1
    end associate
end subroutine append