frame_resize Subroutine

   subroutine frame_resize(this, rows, cols)
      !! Set the frame's dimensions, discarding the diff.
      !!
      !! A resize invalidates the previous frame: the terminal has thrown away
      !! what was on screen, so nothing can be assumed still to be there.
      class(frame_t), intent(inout) :: this
      integer(default_int), intent(in) :: rows
         !! Number of lines; below 0 is treated as 0.
      integer(default_int), intent(in) :: cols
         !! Width in code points; below 0 is treated as 0.

      integer(default_int) :: r, c, i

      r = max(0_default_int, rows)
      c = max(0_default_int, cols)
      if (allocated(this%current)) deallocate (this%current)
      if (allocated(this%shown)) deallocate (this%shown)
      this%rows = r
      this%cols = c
      allocate (this%current(r))
      allocate (this%shown(r))
      do i = 1_default_int, r
         this%current(i) = ""
         this%shown(i) = ""
      end do
      this%full_redraw = .true.
   end subroutine frame_resize