diff --git a/zet.tlv b/zet.tlv
index 6db79ad..78ee02b 100644
--- a/zet.tlv
+++ b/zet.tlv
@@ -2509,120 +2509,6 @@
     >    view_settings.first_zettel = current_zettel_id
     >  end
     >end
-- __teliva_timestamp:
-    >Sat Feb 12 15:04:22 2022
-  editz:
-    >function editz()
-    >  local old_menu = menu
-    >  menu = {
-    >    {'^e', 'finish edit'},
-    >    {'^g', 'cancel edit'},
-    >  }
-    >  local old_data = string.sub(zettels[current_zettel_id].data, 1)
-    >  local top = (render_state.curr_h - 1) * (view_settings.height + view_settings.vmargin)
-    >  local bottom = top + view_settings.height
-    >  local left = (render_state.curr_w - 1) * (view_settings.width + view_settings.hmargin)
-    >  local right = left + view_settings.width
-    >  local cursor = string.len(zettels[current_zettel_id].data)+1
-    >  local quit = false
-    >  curses.curs_set(1)
-    >  while not quit do
-    >    editz_render(window, zettels[current_zettel_id].data, cursor, top, bottom, left, right)
-    >    quit, zettels[current_zettel_id].data, cursor = editz_update(window, zettels[current_zettel_id].data, cursor, old_data)
-    >  end
-    >  curses.curs_set(0)
-    >  menu = old_menu
-    >end
-- __teliva_timestamp:
-    >Sat Feb 12 15:05:20 2022
-  editz_update:
-    >function editz_update(window, prose, cursor, original_prose)
-    >  local key = window:getch()
-    >  local h, w = window:getmaxyx()
-    >  if key == curses.KEY_LEFT then
-    >    if cursor > 1 then
-    >      cursor = cursor-1
-    >    end
-    >  elseif key == curses.KEY_RIGHT then
-    >    if cursor <= #prose then
-    >      cursor = cursor+1
-    >    end
-    >  elseif key == curses.KEY_DOWN then
-    >    cursor = cursor_down(prose, cursor, w)
-    >  elseif key == curses.KEY_UP then
-    >    cursor = cursor_up(prose, cursor, w)
-    >  elseif key == curses.KEY_BACKSPACE or key == 8 or key == 127 then  -- ctrl-h, ctrl-?, delete
-    >    if cursor > 1 then
-    >      cursor = cursor-1
-    >      prose = prose:remove(cursor)
-    >    end
-    >  elseif key == 5 then  -- ctrl-e
-    >    return true, prose, cursor
-    >  elseif key == 7 then  -- ctrl-g
-    >    return true, original_prose, cursor
-    >  elseif key == 10 or (key >= 32 and key < 127) then
-    >    prose = prose:insert(string.char(key), cursor-1)
-    >    cursor = cursor+1
-    >  end
-    >  return false, prose, cursor
-    >end
-- __teliva_timestamp:
-    >Sat Feb 12 15:08:04 2022
-  editz:
-    >function editz()
-    >  local old_menu = menu
-    >  menu = {
-    >    {'^e', 'finish edit'},
-    >    {'^g', 'cancel edit'},
-    >    {'^a', '<<line'},
-    >    {'^b', '<word'},
-    >    {'^f', 'word>'},
-    >    {'^l', 'line>>'},
-    >  }
-    >  local old_data = string.sub(zettels[current_zettel_id].data, 1)
-    >  local top = (render_state.curr_h - 1) * (view_settings.height + view_settings.vmargin)
-    >  local bottom = top + view_settings.height
-    >  local left = (render_state.curr_w - 1) * (view_settings.width + view_settings.hmargin)
-    >  local right = left + view_settings.width
-    >  local cursor = string.len(zettels[current_zettel_id].data)+1
-    >  local quit = false
-    >  curses.curs_set(1)
-    >  while not quit do
-    >    editz_render(window, zettels[current_zettel_id].data, cursor, top, bottom, left, right)
-    >    quit, zettels[current_zettel_id].data, cursor = editz_update(window, zettels[current_zettel_id].data, cursor, old_data)
-    >  end
-    >  curses.curs_set(0)
-    >  menu = old_menu
-    >end
-- __teliva_timestamp:
-    >Sat Feb 12 15:08:58 2022
-  editz:
-    >function editz()
-    >  local old_menu = menu
-    >  menu = {
-    >    {'^e', 'finish edit'},
-    >    {'^g', 'cancel edit'},
-    >    {'^a', '<<line'},
-    >    {'^b', '<word'},
-    >    {'^f', 'word>'},
-    >    {'^l', 'line>>'},
-    >    {'^k/^u', 'del <</>>'},
-    >  }
-    >  local old_data = string.sub(zettels[current_zettel_id].data, 1)
-    >  local top = (render_state.curr_h - 1) * (view_settings.height + view_settings.vmargin)
-    >  local bottom = top + view_settings.height
-    >  local left = (render_state.curr_w - 1) * (view_settings.width + view_settings.hmargin)
-    >  local right = left + view_settings.width
-    >  local cursor = string.len(zettels[current_zettel_id].data)+1
-    >  local quit = false
-    >  curses.curs_set(1)
-    >  while not quit do
-    >    editz_render(window, zettels[current_zettel_id].data, cursor, top, bottom, left, right)
-    >    quit, zettels[current_zettel_id].data, cursor = editz_update(window, zettels[current_zettel_id].data, cursor, old_data)
-    >  end
-    >  curses.curs_set(0)
-    >  menu = old_menu
-    >end
 - __teliva_timestamp:
     >Sat Feb 12 15:11:15 2022
   editz_update:
@@ -2694,202 +2580,6 @@
     >  curses.curs_set(0)
     >  menu = old_menu
     >end
-- __teliva_timestamp:
-    >Sat Feb 12 15:31:27 2022
-  editz_update:
-    >function editz_update(window, prose, cursor, original_prose)
-    >  local key = window:getch()
-    >  local h, w = window:getmaxyx()
-    >  -- cursor movement
-    >  if key == curses.KEY_LEFT then
-    >    if cursor > 1 then
-    >      cursor = cursor-1
-    >    end
-    >  elseif key == curses.KEY_RIGHT then
-    >    if cursor <= #prose then
-    >      cursor = cursor+1
-    >    end
-    >  elseif key == curses.KEY_DOWN then
-    >    cursor = cursor_down(prose, cursor, w)
-    >  elseif key == curses.KEY_UP then
-    >    cursor = cursor_up(prose, cursor, w)
-    >  elseif key == curses.KEY_BACKSPACE or key == 8 or key == 127 then  -- ctrl-h, ctrl-?, delete
-    >    if cursor > 1 then
-    >      cursor = cursor-1
-    >      prose = prose:remove(cursor)
-    >    end
-    >  elseif key == 1 then  -- ctrl-a
-    >    while cursor > 1 and prose[cursor] ~= '\n' do
-    >      cursor = cursor-1
-    >    end
-    >  elseif key == 12 then  -- ctrl-l
-    >  elseif key == 6 then  -- ctrl-f
-    >  elseif key == 2 then  -- ctrl-b
-    >  -- delete
-    >  elseif key == 11 then  -- ctrl-k
-    >  -- exit
-    >  elseif key == 5 then  -- ctrl-e
-    >    return true, prose, cursor
-    >  elseif key == 7 then  -- ctrl-g
-    >    return true, original_prose, cursor
-    >  -- insert
-    >  elseif key == 10 or (key >= 32 and key < 127) then
-    >    prose = prose:insert(string.char(key), cursor-1)
-    >    cursor = cursor+1
-    >  end
-    >  return false, prose, cursor
-    >end
-- __teliva_timestamp:
-    >Sat Feb 12 15:48:35 2022
-  editz_update:
-    >function editz_update(window, prose, cursor, original_prose)
-    >  local key = window:getch()
-    >  local h, w = window:getmaxyx()
-    >  -- cursor movement
-    >  if key == curses.KEY_LEFT then
-    >    if cursor > 1 then
-    >      cursor = cursor-1
-    >    end
-    >  elseif key == curses.KEY_RIGHT then
-    >    if cursor <= #prose then
-    >      cursor = cursor+1
-    >    end
-    >  elseif key == curses.KEY_DOWN then
-    >    cursor = cursor_down(prose, cursor, w)
-    >  elseif key == curses.KEY_UP then
-    >    cursor = cursor_up(prose, cursor, w)
-    >  elseif key == curses.KEY_BACKSPACE or key == 8 or key == 127 then  -- ctrl-h, ctrl-?, delete
-    >    if cursor > 1 then
-    >      cursor = cursor-1
-    >      prose = prose:remove(cursor)
-    >    end
-    >  elseif key == 1 then  -- ctrl-a
-    >    while cursor > 1 do
-    >      if prose[cursor-1] == '\n' then break end
-    >      cursor = cursor-1
-    >    end
-    >  elseif key == 12 then  -- ctrl-l
-    >  elseif key == 6 then  -- ctrl-f
-    >  elseif key == 2 then  -- ctrl-b
-    >  -- delete
-    >  elseif key == 11 then  -- ctrl-k
-    >  -- exit
-    >  elseif key == 5 then  -- ctrl-e
-    >    return true, prose, cursor
-    >  elseif key == 7 then  -- ctrl-g
-    >    return true, original_prose, cursor
-    >  -- insert
-    >  elseif key == 10 or (key >= 32 and key < 127) then
-    >    prose = prose:insert(string.char(key), cursor-1)
-    >    cursor = cursor+1
-    >  end
-    >  return false, prose, cursor
-    >end
-- __teliva_timestamp:
-    >Sat Feb 12 15:49:49 2022
-  editz_update:
-    >function editz_update(window, prose, cursor, original_prose)
-    >  local key = window:getch()
-    >  local h, w = window:getmaxyx()
-    >  -- cursor movement
-    >  if key == curses.KEY_LEFT then
-    >    if cursor > 1 then
-    >      cursor = cursor-1
-    >    end
-    >  elseif key == curses.KEY_RIGHT then
-    >    if cursor <= #prose then
-    >      cursor = cursor+1
-    >    end
-    >  elseif key == curses.KEY_DOWN then
-    >    cursor = cursor_down(prose, cursor, w)
-    >  elseif key == curses.KEY_UP then
-    >    cursor = cursor_up(prose, cursor, w)
-    >  elseif key == curses.KEY_BACKSPACE or key == 8 or key == 127 then  -- ctrl-h, ctrl-?, delete
-    >    if cursor > 1 then
-    >      cursor = cursor-1
-    >      prose = prose:remove(cursor)
-    >    end
-    >  elseif key == 1 then  -- ctrl-a
-    >    while cursor > 1 do
-    >      if prose[cursor-1] == '\n' then break end
-    >      cursor = cursor-1
-    >    end
-    >  elseif key == 12 then  -- ctrl-l
-    >    local max = string.len(prose)
-    >    while cursor <= max and prose[cursor] ~= '\n' do
-    >      cursor = cursor+1
-    >    end
-    >  elseif key == 6 then  -- ctrl-f
-    >  elseif key == 2 then  -- ctrl-b
-    >  -- delete
-    >  elseif key == 11 then  -- ctrl-k
-    >  -- exit
-    >  elseif key == 5 then  -- ctrl-e
-    >    return true, prose, cursor
-    >  elseif key == 7 then  -- ctrl-g
-    >    return true, original_prose, cursor
-    >  -- insert
-    >  elseif key == 10 or (key >= 32 and key < 127) then
-    >    prose = prose:insert(string.char(key), cursor-1)
-    >    cursor = cursor+1
-    >  end
-    >  return false, prose, cursor
-    >end
-- __teliva_timestamp:
-    >Sat Feb 12 15:53:52 2022
-  editz_update:
-    >function editz_update(window, prose, cursor, original_prose)
-    >  local key = window:getch()
-    >  local h, w = window:getmaxyx()
-    >  -- cursor movement
-    >  if key == curses.KEY_LEFT then
-    >    if cursor > 1 then
-    >      cursor = cursor-1
-    >    end
-    >  elseif key == curses.KEY_RIGHT then
-    >    if cursor <= #prose then
-    >      cursor = cursor+1
-    >    end
-    >  elseif key == curses.KEY_DOWN then
-    >    cursor = cursor_down(prose, cursor, w)
-    >  elseif key == curses.KEY_UP then
-    >    cursor = cursor_up(prose, cursor, w)
-    >  elseif key == curses.KEY_BACKSPACE or key == 8 or key == 127 then  -- ctrl-h, ctrl-?, delete
-    >    if cursor > 1 then
-    >      cursor = cursor-1
-    >      prose = prose:remove(cursor)
-    >    end
-    >  elseif key == 1 then  -- ctrl-a
-    >    while cursor > 1 do
-    >      if prose[cursor-1] == '\n' then break end
-    >      cursor = cursor-1
-    >    end
-    >  elseif key == 12 then  -- ctrl-l
-    >    local max = string.len(prose)
-    >    while cursor <= max and prose[cursor] ~= '\n' do
-    >      cursor = cursor+1
-    >    end
-    >  elseif key == 6 then  -- ctrl-f
-    >  elseif key == 2 then  -- ctrl-b
-    >  -- delete
-    >  elseif key == 11 then  -- ctrl-k
-    >    while cursor > 1 do
-    >      if prose[cursor-1] == '\n' then break end
-    >      cursor = cursor-1
-    >      prose = prose:remove(cursor)
-    >    end
-    >  -- exit
-    >  elseif key == 5 then  -- ctrl-e
-    >    return true, prose, cursor
-    >  elseif key == 7 then  -- ctrl-g
-    >    return true, original_prose, cursor
-    >  -- insert
-    >  elseif key == 10 or (key >= 32 and key < 127) then
-    >    prose = prose:insert(string.char(key), cursor-1)
-    >    cursor = cursor+1
-    >  end
-    >  return false, prose, cursor
-    >end
 - __teliva_timestamp:
     >Sat Feb 12 15:55:10 2022
   __teliva_note:
@@ -2945,283 +2635,6 @@
     >  end
     >  return false, prose, cursor
     >end
-- __teliva_timestamp:
-    >Sat Feb 12 16:50:36 2022
-  editz_update:
-    >function editz_update(window, prose, cursor, original_prose)
-    >  local key = window:getch()
-    >  local h, w = window:getmaxyx()
-    >  -- cursor movement
-    >  if key == curses.KEY_LEFT then
-    >    if cursor > 1 then
-    >      cursor = cursor-1
-    >    end
-    >  elseif key == curses.KEY_RIGHT then
-    >    if cursor <= #prose then
-    >      cursor = cursor+1
-    >    end
-    >  elseif key == curses.KEY_DOWN then
-    >    cursor = cursor_down(prose, cursor, w)
-    >  elseif key == curses.KEY_UP then
-    >    cursor = cursor_up(prose, cursor, w)
-    >  elseif key == curses.KEY_BACKSPACE or key == 8 or key == 127 then  -- ctrl-h, ctrl-?, delete
-    >    if cursor > 1 then
-    >      cursor = cursor-1
-    >      prose = prose:remove(cursor)
-    >    end
-    >  elseif key == 1 then  -- ctrl-a
-    >    while cursor > 1 do
-    >      if prose[cursor-1] == '\n' then break end
-    >      cursor = cursor-1
-    >    end
-    >  elseif key == 12 then  -- ctrl-l
-    >    local max = string.len(prose)
-    >    while cursor <= max and prose[cursor] ~= '\n' do
-    >      cursor = cursor+1
-    >    end
-    >  elseif key == 6 then  -- ctrl-f
-    >  elseif key == 2 then  -- ctrl-b
-    >    while cursor > 1 do
-    >      -- first skip all alphanumeric letters
-    >      if string.match(prose[cursor], '%w') then
-    >        cursor = cursor-1
-    >      -- then stop at the last non-alphanumeric letter
-    >      elseif string.match(prose[cursor-1], '%w') then
-    >        break
-    >      else
-    >        cursor = cursor-1
-    >      end
-    >    end
-    >  -- delete
-    >  elseif key == 11 then  -- ctrl-k
-    >    while cursor <= string.len(prose) and prose[cursor] ~= '\n' do
-    >      prose = prose:remove(cursor)
-    >    end
-    >  -- exit
-    >  elseif key == 5 then  -- ctrl-e
-    >    return true, prose, cursor
-    >  elseif key == 7 then  -- ctrl-g
-    >    return true, original_prose, cursor
-    >  -- insert
-    >  elseif key == 10 or (key >= 32 and key < 127) then
-    >    prose = prose:insert(string.char(key), cursor-1)
-    >    cursor = cursor+1
-    >  end
-    >  return false, prose, cursor
-    >end
-- __teliva_timestamp:
-    >Sat Feb 12 16:58:41 2022
-  editz_update:
-    >function editz_update(window, prose, cursor, original_prose)
-    >  local key = window:getch()
-    >  local h, w = window:getmaxyx()
-    >  -- cursor movement
-    >  if key == curses.KEY_LEFT then
-    >    if cursor > 1 then
-    >      cursor = cursor-1
-    >    end
-    >  elseif key == curses.KEY_RIGHT then
-    >    if cursor <= #prose then
-    >      cursor = cursor+1
-    >    end
-    >  elseif key == curses.KEY_DOWN then
-    >    cursor = cursor_down(prose, cursor, w)
-    >  elseif key == curses.KEY_UP then
-    >    cursor = cursor_up(prose, cursor, w)
-    >  elseif key == curses.KEY_BACKSPACE or key == 8 or key == 127 then  -- ctrl-h, ctrl-?, delete
-    >    if cursor > 1 then
-    >      cursor = cursor-1
-    >      prose = prose:remove(cursor)
-    >    end
-    >  elseif key == 1 then  -- ctrl-a
-    >    -- to start of line
-    >    while cursor > 1 do
-    >      if prose[cursor-1] == '\n' then break end
-    >      cursor = cursor-1
-    >    end
-    >  elseif key == 12 then  -- ctrl-l
-    >    -- to end of line
-    >    local max = string.len(prose)
-    >    while cursor <= max and prose[cursor] ~= '\n' do
-    >      cursor = cursor+1
-    >    end
-    >  elseif key == 6 then  -- ctrl-f
-    >    -- to next word
-    >    local max = string.len(prose)
-    >    while cursor <= max and string.match(prose[cursor], '%w') do
-    >      cursor = cursor+1
-    >    end
-    >    while cursor <= max and string.match(prose[cursor], '%W') do
-    >      cursor = cursor+1
-    >    end
-    >  elseif key == 2 then  -- ctrl-b
-    >    -- to previous word
-    >    while cursor > 1 and string.match(prose[cursor], '%W') do
-    >      cursor = cursor-1
-    >    end
-    >    while cursor > 1 and string.match(prose[cursor], '%w') do
-    >      cursor = cursor-1
-    >    end
-    >    while cursor > 1 and string.match(prose[cursor-1], '%w') do
-    >      cursor = cursor-1
-    >    end
-    >  -- delete
-    >  elseif key == 11 then  -- ctrl-k
-    >    while cursor <= string.len(prose) and prose[cursor] ~= '\n' do
-    >      prose = prose:remove(cursor)
-    >    end
-    >  -- exit
-    >  elseif key == 5 then  -- ctrl-e
-    >    return true, prose, cursor
-    >  elseif key == 7 then  -- ctrl-g
-    >    return true, original_prose, cursor
-    >  -- insert
-    >  elseif key == 10 or (key >= 32 and key < 127) then
-    >    prose = prose:insert(string.char(key), cursor-1)
-    >    cursor = cursor+1
-    >  end
-    >  return false, prose, cursor
-    >end
-- __teliva_timestamp:
-    >Sat Feb 12 16:59:37 2022
-  editz_update:
-    >function editz_update(window, prose, cursor, original_prose)
-    >  local key = window:getch()
-    >  local h, w = window:getmaxyx()
-    >  -- cursor movement
-    >  if key == curses.KEY_LEFT then
-    >    if cursor > 1 then
-    >      cursor = cursor-1
-    >    end
-    >  elseif key == curses.KEY_RIGHT then
-    >    if cursor <= #prose then
-    >      cursor = cursor+1
-    >    end
-    >  elseif key == curses.KEY_DOWN then
-    >    cursor = cursor_down(prose, cursor, w)
-    >  elseif key == curses.KEY_UP then
-    >    cursor = cursor_up(prose, cursor, w)
-    >  elseif key == curses.KEY_BACKSPACE or key == 8 or key == 127 then  -- ctrl-h, ctrl-?, delete
-    >    if cursor > 1 then
-    >      cursor = cursor-1
-    >      prose = prose:remove(cursor)
-    >    end
-    >  elseif key == 1 then  -- ctrl-a
-    >    -- to start of line
-    >    while cursor > 1 do
-    >      if prose[cursor-1] == '\n' then break end
-    >      cursor = cursor-1
-    >    end
-    >  elseif key == 12 then  -- ctrl-l
-    >    -- to end of line
-    >    local max = string.len(prose)
-    >    while cursor <= max and prose[cursor] ~= '\n' do
-    >      cursor = cursor+1
-    >    end
-    >  elseif key == 6 then  -- ctrl-f
-    >    -- to next word
-    >    local max = string.len(prose)
-    >    while cursor <= max and string.match(prose[cursor], '%w') do
-    >      cursor = cursor+1
-    >    end
-    >    while cursor <= max and string.match(prose[cursor], '%W') do
-    >      cursor = cursor+1
-    >    end
-    >  elseif key == 2 then  -- ctrl-b
-    >    -- to previous word
-    >    while cursor > 1 and string.match(prose[cursor], '%W') do
-    >      cursor = cursor-1
-    >    end
-    >    while cursor > 1 and string.match(prose[cursor-1], '%w') do
-    >      cursor = cursor-1
-    >    end
-    >  -- delete
-    >  elseif key == 11 then  -- ctrl-k
-    >    while cursor <= string.len(prose) and prose[cursor] ~= '\n' do
-    >      prose = prose:remove(cursor)
-    >    end
-    >  -- exit
-    >  elseif key == 5 then  -- ctrl-e
-    >    return true, prose, cursor
-    >  elseif key == 7 then  -- ctrl-g
-    >    return true, original_prose, cursor
-    >  -- insert
-    >  elseif key == 10 or (key >= 32 and key < 127) then
-    >    prose = prose:insert(string.char(key), cursor-1)
-    >    cursor = cursor+1
-    >  end
-    >  return false, prose, cursor
-    >end
-- __teliva_timestamp:
-    >Sat Feb 12 17:00:00 2022
-  editz_update:
-    >function editz_update(window, prose, cursor, original_prose)
-    >  local key = window:getch()
-    >  local h, w = window:getmaxyx()
-    >  -- cursor movement
-    >  if key == curses.KEY_LEFT then
-    >    if cursor > 1 then
-    >      cursor = cursor-1
-    >    end
-    >  elseif key == curses.KEY_RIGHT then
-    >    if cursor <= #prose then
-    >      cursor = cursor+1
-    >    end
-    >  elseif key == curses.KEY_DOWN then
-    >    cursor = cursor_down(prose, cursor, w)
-    >  elseif key == curses.KEY_UP then
-    >    cursor = cursor_up(prose, cursor, w)
-    >  elseif key == curses.KEY_BACKSPACE or key == 8 or key == 127 then  -- ctrl-h, ctrl-?, delete
-    >    if cursor > 1 then
-    >      cursor = cursor-1
-    >      prose = prose:remove(cursor)
-    >    end
-    >  elseif key == 1 then  -- ctrl-a
-    >    -- to start of line
-    >    while cursor > 1 do
-    >      if prose[cursor-1] == '\n' then break end
-    >      cursor = cursor-1
-    >    end
-    >  elseif key == 12 then  -- ctrl-l
-    >    -- to end of line
-    >    local max = string.len(prose)
-    >    while cursor <= max and prose[cursor] ~= '\n' do
-    >      cursor = cursor+1
-    >    end
-    >  elseif key == 6 then  -- ctrl-f
-    >    -- to next word
-    >    local max = string.len(prose)
-    >    while cursor <= max and string.match(prose[cursor], '%w') do
-    >      cursor = cursor+1
-    >    end
-    >    while cursor <= max and string.match(prose[cursor], '%W') do
-    >      cursor = cursor+1
-    >    end
-    >  elseif key == 2 then  -- ctrl-b
-    >    -- to previous word
-    >    while cursor > 1 and string.match(prose[cursor], '%W') do
-    >      cursor = cursor-1
-    >    end
-    >    while cursor > 1 and string.match(prose[cursor], '%w') do
-    >      cursor = cursor-1
-    >    end
-    >  -- delete
-    >  elseif key == 11 then  -- ctrl-k
-    >    while cursor <= string.len(prose) and prose[cursor] ~= '\n' do
-    >      prose = prose:remove(cursor)
-    >    end
-    >  -- exit
-    >  elseif key == 5 then  -- ctrl-e
-    >    return true, prose, cursor
-    >  elseif key == 7 then  -- ctrl-g
-    >    return true, original_prose, cursor
-    >  -- insert
-    >  elseif key == 10 or (key >= 32 and key < 127) then
-    >    prose = prose:insert(string.char(key), cursor-1)
-    >    cursor = cursor+1
-    >  end
-    >  return false, prose, cursor
-    >end
 - __teliva_timestamp:
     >Sat Feb 12 17:01:45 2022
   __teliva_note:
@@ -3419,147 +2832,6 @@
     >  end
     >  window:refresh()
     >end
-- __teliva_timestamp:
-    >Sat Feb 12 17:17:45 2022
-  update:
-    >function update(window)
-    >  local key = window:getch()
-    >  local h, w = window:getmaxyx()
-    >  local curr = zettels[current_zettel_id]
-    >  assert(curr, string.format('cursor fell off the edge of the world: %s', type(current_zettel_id)))
-    >  -- move along the graph
-    >  if key == string.byte('j') then
-    >    if curr.child then
-    >      current_zettel_id = curr.child
-    >    elseif curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >  elseif key == string.byte('k') then
-    >    if curr.parent then
-    >      current_zettel_id = curr.parent
-    >    end
-    >  elseif key == string.byte('h') then
-    >    if curr.prev then
-    >      current_zettel_id = curr.prev
-    >    elseif curr.parent then
-    >      current_zettel_id = curr.parent
-    >    end
-    >  elseif key == string.byte('l') then
-    >    if curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    if not render_state.displayed[current_zettel_id] then
-    >      rend
-    >  -- move along the screen
-    >  elseif key == curses.KEY_UP then
-    >    if render_state.curr_h > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h - 1]
-    >    end
-    >  elseif key == curses.KEY_DOWN then
-    >    if render_state.wh2id[render_state.curr_w][render_state.curr_h + 1] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h + 1]
-    >    end
-    >  elseif key == curses.KEY_LEFT then
-    >    if render_state.curr_w > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w - 1][render_state.curr_h]
-    >    end
-    >  elseif key == curses.KEY_RIGHT then
-    >    if render_state.wh2id[render_state.curr_w + 1] and render_state.wh2id[render_state.curr_w + 1][render_state.curr_h] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w + 1][render_state.curr_h]
-    >    end
-    >  -- mutations
-    >  elseif key == string.byte('e') then
-    >    editz(window)
-    >  elseif key == string.byte('a') then
-    >    -- insert sibling after
-    >    local old = curr.next
-    >    curr.next = new_id()
-    >    local new = zettels[curr.next]
-    >    new.data = ''
-    >    new.next = old
-    >    new.prev = current_zettel_id
-    >    if old then
-    >      zettels[old].prev = curr.next
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.next
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('b') then
-    >    -- insert sibling before
-    >    local old = curr.prev
-    >    curr.prev = new_id()
-    >    local new = zettels[curr.prev]
-    >    new.data = ''
-    >    new.prev = old
-    >    new.next = current_zettel_id
-    >    if old then
-    >      zettels[old].next = curr.prev
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.prev
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('c') then
-    >    -- insert child
-    >    local old = curr.child
-    >    curr.child = new_id()
-    >    local new = zettels[curr.child]
-    >    new.data = ''
-    >    new.next = old
-    >    if old then
-    >      assert(zettels[old].prev == nil, "first child shouldn't have a previous sibling")
-    >      zettels[old].prev = curr.child
-    >    end
-    >    new.parent = current_zettel_id
-    >    current_zettel_id = curr.child
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  -- cross-links
-    >  elseif key == string.byte('s') then
-    >    -- save zettel to a stash
-    >    stash = current_zettel_id
-    >  elseif key == string.byte('t') then
-    >    -- cross-link a zettel bidirectionally with what's on the stash
-    >    local insert_crosslink =
-    >      function(a, rel, b_id)
-    >        if a.crosslinks == nil then
-    >          a.crosslinks = {}
-    >        end
-    >        a.crosslinks[rel] = b_id
-    >      end
-    >    insert_crosslink(curr, 'a', stash)
-    >    insert_crosslink(zettels[stash], 'a', current_zettel_id)
-    >    stash = nil
-    >  -- view settings
-    >  elseif key == string.byte('x') then
-    >    if view_settings.width > 5 then
-    >      view_settings.width = view_settings.width - 5
-    >    end
-    >  elseif key == string.byte('X') then
-    >    if view_settings.width < w-5 then
-    >      view_settings.width = view_settings.width + 5
-    >    end
-    >  elseif key == string.byte('y') then
-    >    if view_settings.height > 0 then
-    >      view_settings.height = view_settings.height - 1
-    >    end
-    >  elseif key == string.byte('Y') then
-    >    if view_settings.height < h-2 then
-    >      view_settings.height = view_settings.height + 1
-    >    end
-    >  elseif key == string.byte('z') then
-    >    -- scroll to show the current zettel at top of screen
-    >    -- often has the effect of zooming in on its hierarchy
-    >    view_settings.first_zettel = current_zettel_id
-    >  end
-    >end
 - __teliva_timestamp:
     >Sat Feb 12 17:18:34 2022
   __teliva_note:
@@ -3717,163 +2989,6 @@
     >    view_settings.first_zettel = current_zettel_id
     >  end
     >end
-- __teliva_timestamp:
-    >Sat Feb 12 17:21:48 2022
-  update:
-    >function update(window)
-    >  local key = window:getch()
-    >  local h, w = window:getmaxyx()
-    >  local curr = zettels[current_zettel_id]
-    >  assert(curr, string.format('cursor fell off the edge of the world: %s', type(current_zettel_id)))
-    >  -- move along the graph
-    >  if key == string.byte('j') then
-    >    if curr.child then
-    >      current_zettel_id = curr.child
-    >    elseif curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('k') then
-    >    if curr.parent then
-    >      current_zettel_id = curr.parent
-    >    elseif curr.prev then
-    >      current_zettel_id = curr.prev
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('h') then
-    >    if curr.prev then
-    >      current_zettel_id = curr.prev
-    >    elseif curr.parent then
-    >      current_zettel_id = curr.parent
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('l') then
-    >    if curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  -- move along the screen
-    >  elseif key == curses.KEY_UP then
-    >    if render_state.curr_h > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h - 1]
-    >    end
-    >  elseif key == curses.KEY_DOWN then
-    >    if render_state.wh2id[render_state.curr_w][render_state.curr_h + 1] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h + 1]
-    >    end
-    >  elseif key == curses.KEY_LEFT then
-    >    if render_state.curr_w > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w - 1][render_state.curr_h]
-    >    end
-    >  elseif key == curses.KEY_RIGHT then
-    >    if render_state.wh2id[render_state.curr_w + 1] and render_state.wh2id[render_state.curr_w + 1][render_state.curr_h] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w + 1][render_state.curr_h]
-    >    end
-    >  -- mutations
-    >  elseif key == string.byte('e') then
-    >    editz(window)
-    >  elseif key == string.byte('a') then
-    >    -- insert sibling after
-    >    local old = curr.next
-    >    curr.next = new_id()
-    >    local new = zettels[curr.next]
-    >    new.data = ''
-    >    new.next = old
-    >    new.prev = current_zettel_id
-    >    if old then
-    >      zettels[old].prev = curr.next
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.next
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('b') then
-    >    -- insert sibling before
-    >    local old = curr.prev
-    >    curr.prev = new_id()
-    >    local new = zettels[curr.prev]
-    >    new.data = ''
-    >    new.prev = old
-    >    new.next = current_zettel_id
-    >    if old then
-    >      zettels[old].next = curr.prev
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.prev
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('c') then
-    >    -- insert child
-    >    local old = curr.child
-    >    curr.child = new_id()
-    >    local new = zettels[curr.child]
-    >    new.data = ''
-    >    new.next = old
-    >    if old then
-    >      assert(zettels[old].prev == nil, "first child shouldn't have a previous sibling")
-    >      zettels[old].prev = curr.child
-    >    end
-    >    new.parent = current_zettel_id
-    >    current_zettel_id = curr.child
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  -- cross-links
-    >  elseif key == string.byte('s') then
-    >    -- save zettel to a stash
-    >    stash = current_zettel_id
-    >  elseif key == string.byte('t') then
-    >    -- cross-link a zettel bidirectionally with what's on the stash
-    >    local insert_crosslink =
-    >      function(a, rel, b_id)
-    >        if a.crosslinks == nil then
-    >          a.crosslinks = {}
-    >        end
-    >        a.crosslinks[rel] = b_id
-    >      end
-    >    insert_crosslink(curr, 'a', stash)
-    >    insert_crosslink(zettels[stash], 'a', current_zettel_id)
-    >    stash = nil
-    >  -- view settings
-    >  elseif key == string.byte('x') then
-    >    if view_settings.width > 5 then
-    >      view_settings.width = view_settings.width - 5
-    >    end
-    >  elseif key == string.byte('X') then
-    >    if view_settings.width < w-5 then
-    >      view_settings.width = view_settings.width + 5
-    >    end
-    >  elseif key == string.byte('y') then
-    >    if view_settings.height > 0 then
-    >      view_settings.height = view_settings.height - 1
-    >    end
-    >  elseif key == string.byte('Y') then
-    >    if view_settings.height < h-2 then
-    >      view_settings.height = view_settings.height + 1
-    >    end
-    >  elseif key == string.byte('z') then
-    >    -- scroll to show the current zettel at top of screen
-    >    -- often has the effect of zooming in on its hierarchy
-    >    view_settings.first_zettel = current_zettel_id
-    >  end
-    >end
 - __teliva_timestamp:
     >Sat Feb 12 17:23:33 2022
   __teliva_note:
@@ -4054,2150 +3169,6 @@
     >  {'t', 'link with stash'},
     >  {'z', 'scroll'},
     >}
-- __teliva_timestamp:
-    >Sat Feb 12 17:30:55 2022
-  render_state:
-    >-- some information about what's been drawn on screen
-    >-- not saved between app restarts
-    >render_state = {
-    >  -- where the current zettel is, in units of zettels
-    >  curr_h = 1,
-    >  curr_w = 1,
-    >  -- what zettel is at each position on screen, in units of zettels
-    >  hw2id = {},
-    >  -- list of zettels currently displayed
-    >  displayed = {},
-    >  -- history of screen render state
-    >  history = {},  -- we just need view_settings.first_zettel and current_zettel_id
-    >}
-- __teliva_timestamp:
-    >Sat Feb 12 17:46:09 2022
-  update:
-    >function update(window)
-    >  local key = window:getch()
-    >  local h, w = window:getmaxyx()
-    >  local curr = zettels[current_zettel_id]
-    >  assert(curr, string.format('cursor fell off the edge of the world: %s', type(current_zettel_id)))
-    >  -- read from or write to render_state.history
-    >  if key == string.byte('<') then
-    >    -- previous zettel moved to
-    >    -- does NOT undo mutations
-    >    if #render_state.history > 0 then
-    >      view_settings.first_zettel = render_state.history[-1].first_zettel
-    >      current_zettel_id = render_state.history[-1].current_zettel_id
-    >      render_state.history:remove()
-    >    end
-    >    return
-    >  end
-    >  if key ~= string.byte('e') then
-    >    render_state.history:insert(view_settings.first_zettel, current_zettel_id)
-    >  end
-    >  -- move along the graph
-    >  if key == string.byte('j') then
-    >    -- child or next sibling
-    >    if curr.child then
-    >      current_zettel_id = curr.child
-    >    elseif curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('k') then
-    >    -- parent or previous sibling
-    >    if curr.parent then
-    >      current_zettel_id = curr.parent
-    >    elseif curr.prev then
-    >      current_zettel_id = curr.prev
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('h') then
-    >    -- previous sibling or parent
-    >    if curr.prev then
-    >      current_zettel_id = curr.prev
-    >    elseif curr.parent then
-    >      current_zettel_id = curr.parent
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('l') then
-    >    -- next sibling or next sibling of parent
-    >    if curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  -- move along the screen
-    >  elseif key == curses.KEY_UP then
-    >    if render_state.curr_h > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h - 1]
-    >    end
-    >  elseif key == curses.KEY_DOWN then
-    >    if render_state.wh2id[render_state.curr_w][render_state.curr_h + 1] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h + 1]
-    >    end
-    >  elseif key == curses.KEY_LEFT then
-    >    if render_state.curr_w > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w - 1][render_state.curr_h]
-    >    end
-    >  elseif key == curses.KEY_RIGHT then
-    >    if render_state.wh2id[render_state.curr_w + 1] and render_state.wh2id[render_state.curr_w + 1][render_state.curr_h] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w + 1][render_state.curr_h]
-    >    end
-    >  -- mutations
-    >  elseif key == string.byte('e') then
-    >    editz(window)
-    >  elseif key == string.byte('a') then
-    >    -- insert sibling after
-    >    local old = curr.next
-    >    curr.next = new_id()
-    >    local new = zettels[curr.next]
-    >    new.data = ''
-    >    new.next = old
-    >    new.prev = current_zettel_id
-    >    if old then
-    >      zettels[old].prev = curr.next
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.next
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('b') then
-    >    -- insert sibling before
-    >    local old = curr.prev
-    >    curr.prev = new_id()
-    >    local new = zettels[curr.prev]
-    >    new.data = ''
-    >    new.prev = old
-    >    new.next = current_zettel_id
-    >    if old then
-    >      zettels[old].next = curr.prev
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.prev
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('c') then
-    >    -- insert child
-    >    local old = curr.child
-    >    curr.child = new_id()
-    >    local new = zettels[curr.child]
-    >    new.data = ''
-    >    new.next = old
-    >    if old then
-    >      assert(zettels[old].prev == nil, "first child shouldn't have a previous sibling")
-    >      zettels[old].prev = curr.child
-    >    end
-    >    new.parent = current_zettel_id
-    >    current_zettel_id = curr.child
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  -- cross-links
-    >  elseif key == string.byte('s') then
-    >    -- save zettel to a stash
-    >    stash = current_zettel_id
-    >  elseif key == string.byte('t') then
-    >    -- cross-link a zettel bidirectionally with what's on the stash
-    >    local insert_crosslink =
-    >      function(a, rel, b_id)
-    >        if a.crosslinks == nil then
-    >          a.crosslinks = {}
-    >        end
-    >        a.crosslinks[rel] = b_id
-    >      end
-    >    insert_crosslink(curr, 'a', stash)
-    >    insert_crosslink(zettels[stash], 'a', current_zettel_id)
-    >    stash = nil
-    >  -- view settings
-    >  elseif key == string.byte('x') then
-    >    if view_settings.width > 5 then
-    >      view_settings.width = view_settings.width - 5
-    >    end
-    >  elseif key == string.byte('X') then
-    >    if view_settings.width < w-5 then
-    >      view_settings.width = view_settings.width + 5
-    >    end
-    >  elseif key == string.byte('y') then
-    >    if view_settings.height > 0 then
-    >      view_settings.height = view_settings.height - 1
-    >    end
-    >  elseif key == string.byte('Y') then
-    >    if view_settings.height < h-2 then
-    >      view_settings.height = view_settings.height + 1
-    >    end
-    >  elseif key == string.byte('z') then
-    >    -- scroll to show the current zettel at top of screen
-    >    -- often has the effect of zooming in on its hierarchy
-    >    view_settings.first_zettel = current_zettel_id
-    >  end
-    >end
-- __teliva_timestamp:
-    >Sat Feb 12 17:47:08 2022
-  update:
-    >function update(window)
-    >  local key = window:getch()
-    >  local h, w = window:getmaxyx()
-    >  local curr = zettels[current_zettel_id]
-    >  assert(curr, string.format('cursor fell off the edge of the world: %s', type(current_zettel_id)))
-    >  -- read from or write to render_state.history
-    >  if key == string.byte('<') then
-    >    -- previous zettel moved to
-    >    -- does NOT undo mutations
-    >    if #render_state.history > 0 then
-    >      view_settings.first_zettel = render_state.history[-1].first_zettel
-    >      current_zettel_id = render_state.history[-1].current_zettel_id
-    >      render_state.history:remove()
-    >    end
-    >    return
-    >  end
-    >  if key ~= string.byte('e') then
-    >    render_state.history:insert({first_zettel=view_settings.first_zettel, current_zettel_id=current_zettel_id})
-    >  end
-    >  -- move along the graph
-    >  if key == string.byte('j') then
-    >    -- child or next sibling
-    >    if curr.child then
-    >      current_zettel_id = curr.child
-    >    elseif curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('k') then
-    >    -- parent or previous sibling
-    >    if curr.parent then
-    >      current_zettel_id = curr.parent
-    >    elseif curr.prev then
-    >      current_zettel_id = curr.prev
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('h') then
-    >    -- previous sibling or parent
-    >    if curr.prev then
-    >      current_zettel_id = curr.prev
-    >    elseif curr.parent then
-    >      current_zettel_id = curr.parent
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('l') then
-    >    -- next sibling or next sibling of parent
-    >    if curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  -- move along the screen
-    >  elseif key == curses.KEY_UP then
-    >    if render_state.curr_h > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h - 1]
-    >    end
-    >  elseif key == curses.KEY_DOWN then
-    >    if render_state.wh2id[render_state.curr_w][render_state.curr_h + 1] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h + 1]
-    >    end
-    >  elseif key == curses.KEY_LEFT then
-    >    if render_state.curr_w > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w - 1][render_state.curr_h]
-    >    end
-    >  elseif key == curses.KEY_RIGHT then
-    >    if render_state.wh2id[render_state.curr_w + 1] and render_state.wh2id[render_state.curr_w + 1][render_state.curr_h] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w + 1][render_state.curr_h]
-    >    end
-    >  -- mutations
-    >  elseif key == string.byte('e') then
-    >    editz(window)
-    >  elseif key == string.byte('a') then
-    >    -- insert sibling after
-    >    local old = curr.next
-    >    curr.next = new_id()
-    >    local new = zettels[curr.next]
-    >    new.data = ''
-    >    new.next = old
-    >    new.prev = current_zettel_id
-    >    if old then
-    >      zettels[old].prev = curr.next
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.next
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('b') then
-    >    -- insert sibling before
-    >    local old = curr.prev
-    >    curr.prev = new_id()
-    >    local new = zettels[curr.prev]
-    >    new.data = ''
-    >    new.prev = old
-    >    new.next = current_zettel_id
-    >    if old then
-    >      zettels[old].next = curr.prev
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.prev
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('c') then
-    >    -- insert child
-    >    local old = curr.child
-    >    curr.child = new_id()
-    >    local new = zettels[curr.child]
-    >    new.data = ''
-    >    new.next = old
-    >    if old then
-    >      assert(zettels[old].prev == nil, "first child shouldn't have a previous sibling")
-    >      zettels[old].prev = curr.child
-    >    end
-    >    new.parent = current_zettel_id
-    >    current_zettel_id = curr.child
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  -- cross-links
-    >  elseif key == string.byte('s') then
-    >    -- save zettel to a stash
-    >    stash = current_zettel_id
-    >  elseif key == string.byte('t') then
-    >    -- cross-link a zettel bidirectionally with what's on the stash
-    >    local insert_crosslink =
-    >      function(a, rel, b_id)
-    >        if a.crosslinks == nil then
-    >          a.crosslinks = {}
-    >        end
-    >        a.crosslinks[rel] = b_id
-    >      end
-    >    insert_crosslink(curr, 'a', stash)
-    >    insert_crosslink(zettels[stash], 'a', current_zettel_id)
-    >    stash = nil
-    >  -- view settings
-    >  elseif key == string.byte('x') then
-    >    if view_settings.width > 5 then
-    >      view_settings.width = view_settings.width - 5
-    >    end
-    >  elseif key == string.byte('X') then
-    >    if view_settings.width < w-5 then
-    >      view_settings.width = view_settings.width + 5
-    >    end
-    >  elseif key == string.byte('y') then
-    >    if view_settings.height > 0 then
-    >      view_settings.height = view_settings.height - 1
-    >    end
-    >  elseif key == string.byte('Y') then
-    >    if view_settings.height < h-2 then
-    >      view_settings.height = view_settings.height + 1
-    >    end
-    >  elseif key == string.byte('z') then
-    >    -- scroll to show the current zettel at top of screen
-    >    -- often has the effect of zooming in on its hierarchy
-    >    view_settings.first_zettel = current_zettel_id
-    >  end
-    >end
-- __teliva_timestamp:
-    >Sat Feb 12 17:48:38 2022
-  update:
-    >function update(window)
-    >  local key = window:getch()
-    >  local h, w = window:getmaxyx()
-    >  local curr = zettels[current_zettel_id]
-    >  assert(curr, string.format('cursor fell off the edge of the world: %s', type(current_zettel_id)))
-    >  -- read from or write to render_state.history
-    >  if key == string.byte('<') then
-    >    -- previous zettel moved to
-    >    -- does NOT undo mutations
-    >    if #render_state.history > 0 then
-    >      view_settings.first_zettel = render_state.history[-1].first_zettel
-    >      current_zettel_id = render_state.history[-1].current_zettel_id
-    >      render_state.history:remove()
-    >    end
-    >    return
-    >  end
-    >  if key ~= string.byte('e') then
-    >    window:mvaddstr(30, 60, renderstate.history)
-    >    window:getch()
-    >    render_state.history:insert({first_zettel=view_settings.first_zettel, current_zettel_id=current_zettel_id})
-    >  end
-    >  -- move along the graph
-    >  if key == string.byte('j') then
-    >    -- child or next sibling
-    >    if curr.child then
-    >      current_zettel_id = curr.child
-    >    elseif curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('k') then
-    >    -- parent or previous sibling
-    >    if curr.parent then
-    >      current_zettel_id = curr.parent
-    >    elseif curr.prev then
-    >      current_zettel_id = curr.prev
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('h') then
-    >    -- previous sibling or parent
-    >    if curr.prev then
-    >      current_zettel_id = curr.prev
-    >    elseif curr.parent then
-    >      current_zettel_id = curr.parent
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('l') then
-    >    -- next sibling or next sibling of parent
-    >    if curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  -- move along the screen
-    >  elseif key == curses.KEY_UP then
-    >    if render_state.curr_h > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h - 1]
-    >    end
-    >  elseif key == curses.KEY_DOWN then
-    >    if render_state.wh2id[render_state.curr_w][render_state.curr_h + 1] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h + 1]
-    >    end
-    >  elseif key == curses.KEY_LEFT then
-    >    if render_state.curr_w > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w - 1][render_state.curr_h]
-    >    end
-    >  elseif key == curses.KEY_RIGHT then
-    >    if render_state.wh2id[render_state.curr_w + 1] and render_state.wh2id[render_state.curr_w + 1][render_state.curr_h] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w + 1][render_state.curr_h]
-    >    end
-    >  -- mutations
-    >  elseif key == string.byte('e') then
-    >    editz(window)
-    >  elseif key == string.byte('a') then
-    >    -- insert sibling after
-    >    local old = curr.next
-    >    curr.next = new_id()
-    >    local new = zettels[curr.next]
-    >    new.data = ''
-    >    new.next = old
-    >    new.prev = current_zettel_id
-    >    if old then
-    >      zettels[old].prev = curr.next
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.next
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('b') then
-    >    -- insert sibling before
-    >    local old = curr.prev
-    >    curr.prev = new_id()
-    >    local new = zettels[curr.prev]
-    >    new.data = ''
-    >    new.prev = old
-    >    new.next = current_zettel_id
-    >    if old then
-    >      zettels[old].next = curr.prev
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.prev
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('c') then
-    >    -- insert child
-    >    local old = curr.child
-    >    curr.child = new_id()
-    >    local new = zettels[curr.child]
-    >    new.data = ''
-    >    new.next = old
-    >    if old then
-    >      assert(zettels[old].prev == nil, "first child shouldn't have a previous sibling")
-    >      zettels[old].prev = curr.child
-    >    end
-    >    new.parent = current_zettel_id
-    >    current_zettel_id = curr.child
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  -- cross-links
-    >  elseif key == string.byte('s') then
-    >    -- save zettel to a stash
-    >    stash = current_zettel_id
-    >  elseif key == string.byte('t') then
-    >    -- cross-link a zettel bidirectionally with what's on the stash
-    >    local insert_crosslink =
-    >      function(a, rel, b_id)
-    >        if a.crosslinks == nil then
-    >          a.crosslinks = {}
-    >        end
-    >        a.crosslinks[rel] = b_id
-    >      end
-    >    insert_crosslink(curr, 'a', stash)
-    >    insert_crosslink(zettels[stash], 'a', current_zettel_id)
-    >    stash = nil
-    >  -- view settings
-    >  elseif key == string.byte('x') then
-    >    if view_settings.width > 5 then
-    >      view_settings.width = view_settings.width - 5
-    >    end
-    >  elseif key == string.byte('X') then
-    >    if view_settings.width < w-5 then
-    >      view_settings.width = view_settings.width + 5
-    >    end
-    >  elseif key == string.byte('y') then
-    >    if view_settings.height > 0 then
-    >      view_settings.height = view_settings.height - 1
-    >    end
-    >  elseif key == string.byte('Y') then
-    >    if view_settings.height < h-2 then
-    >      view_settings.height = view_settings.height + 1
-    >    end
-    >  elseif key == string.byte('z') then
-    >    -- scroll to show the current zettel at top of screen
-    >    -- often has the effect of zooming in on its hierarchy
-    >    view_settings.first_zettel = current_zettel_id
-    >  end
-    >end
-- __teliva_timestamp:
-    >Sat Feb 12 17:48:50 2022
-  update:
-    >function update(window)
-    >  local key = window:getch()
-    >  local h, w = window:getmaxyx()
-    >  local curr = zettels[current_zettel_id]
-    >  assert(curr, string.format('cursor fell off the edge of the world: %s', type(current_zettel_id)))
-    >  -- read from or write to render_state.history
-    >  if key == string.byte('<') then
-    >    -- previous zettel moved to
-    >    -- does NOT undo mutations
-    >    if #render_state.history > 0 then
-    >      view_settings.first_zettel = render_state.history[-1].first_zettel
-    >      current_zettel_id = render_state.history[-1].current_zettel_id
-    >      render_state.history:remove()
-    >    end
-    >    return
-    >  end
-    >  if key ~= string.byte('e') then
-    >    window:mvaddstr(30, 60, render_state.history)
-    >    window:getch()
-    >    render_state.history:insert({first_zettel=view_settings.first_zettel, current_zettel_id=current_zettel_id})
-    >  end
-    >  -- move along the graph
-    >  if key == string.byte('j') then
-    >    -- child or next sibling
-    >    if curr.child then
-    >      current_zettel_id = curr.child
-    >    elseif curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('k') then
-    >    -- parent or previous sibling
-    >    if curr.parent then
-    >      current_zettel_id = curr.parent
-    >    elseif curr.prev then
-    >      current_zettel_id = curr.prev
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('h') then
-    >    -- previous sibling or parent
-    >    if curr.prev then
-    >      current_zettel_id = curr.prev
-    >    elseif curr.parent then
-    >      current_zettel_id = curr.parent
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('l') then
-    >    -- next sibling or next sibling of parent
-    >    if curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  -- move along the screen
-    >  elseif key == curses.KEY_UP then
-    >    if render_state.curr_h > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h - 1]
-    >    end
-    >  elseif key == curses.KEY_DOWN then
-    >    if render_state.wh2id[render_state.curr_w][render_state.curr_h + 1] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h + 1]
-    >    end
-    >  elseif key == curses.KEY_LEFT then
-    >    if render_state.curr_w > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w - 1][render_state.curr_h]
-    >    end
-    >  elseif key == curses.KEY_RIGHT then
-    >    if render_state.wh2id[render_state.curr_w + 1] and render_state.wh2id[render_state.curr_w + 1][render_state.curr_h] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w + 1][render_state.curr_h]
-    >    end
-    >  -- mutations
-    >  elseif key == string.byte('e') then
-    >    editz(window)
-    >  elseif key == string.byte('a') then
-    >    -- insert sibling after
-    >    local old = curr.next
-    >    curr.next = new_id()
-    >    local new = zettels[curr.next]
-    >    new.data = ''
-    >    new.next = old
-    >    new.prev = current_zettel_id
-    >    if old then
-    >      zettels[old].prev = curr.next
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.next
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('b') then
-    >    -- insert sibling before
-    >    local old = curr.prev
-    >    curr.prev = new_id()
-    >    local new = zettels[curr.prev]
-    >    new.data = ''
-    >    new.prev = old
-    >    new.next = current_zettel_id
-    >    if old then
-    >      zettels[old].next = curr.prev
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.prev
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('c') then
-    >    -- insert child
-    >    local old = curr.child
-    >    curr.child = new_id()
-    >    local new = zettels[curr.child]
-    >    new.data = ''
-    >    new.next = old
-    >    if old then
-    >      assert(zettels[old].prev == nil, "first child shouldn't have a previous sibling")
-    >      zettels[old].prev = curr.child
-    >    end
-    >    new.parent = current_zettel_id
-    >    current_zettel_id = curr.child
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  -- cross-links
-    >  elseif key == string.byte('s') then
-    >    -- save zettel to a stash
-    >    stash = current_zettel_id
-    >  elseif key == string.byte('t') then
-    >    -- cross-link a zettel bidirectionally with what's on the stash
-    >    local insert_crosslink =
-    >      function(a, rel, b_id)
-    >        if a.crosslinks == nil then
-    >          a.crosslinks = {}
-    >        end
-    >        a.crosslinks[rel] = b_id
-    >      end
-    >    insert_crosslink(curr, 'a', stash)
-    >    insert_crosslink(zettels[stash], 'a', current_zettel_id)
-    >    stash = nil
-    >  -- view settings
-    >  elseif key == string.byte('x') then
-    >    if view_settings.width > 5 then
-    >      view_settings.width = view_settings.width - 5
-    >    end
-    >  elseif key == string.byte('X') then
-    >    if view_settings.width < w-5 then
-    >      view_settings.width = view_settings.width + 5
-    >    end
-    >  elseif key == string.byte('y') then
-    >    if view_settings.height > 0 then
-    >      view_settings.height = view_settings.height - 1
-    >    end
-    >  elseif key == string.byte('Y') then
-    >    if view_settings.height < h-2 then
-    >      view_settings.height = view_settings.height + 1
-    >    end
-    >  elseif key == string.byte('z') then
-    >    -- scroll to show the current zettel at top of screen
-    >    -- often has the effect of zooming in on its hierarchy
-    >    view_settings.first_zettel = current_zettel_id
-    >  end
-    >end
-- __teliva_timestamp:
-    >Sat Feb 12 17:49:04 2022
-  update:
-    >function update(window)
-    >  local key = window:getch()
-    >  local h, w = window:getmaxyx()
-    >  local curr = zettels[current_zettel_id]
-    >  assert(curr, string.format('cursor fell off the edge of the world: %s', type(current_zettel_id)))
-    >  -- read from or write to render_state.history
-    >  if key == string.byte('<') then
-    >    -- previous zettel moved to
-    >    -- does NOT undo mutations
-    >    if #render_state.history > 0 then
-    >      view_settings.first_zettel = render_state.history[-1].first_zettel
-    >      current_zettel_id = render_state.history[-1].current_zettel_id
-    >      render_state.history:remove()
-    >    end
-    >    return
-    >  end
-    >  if key ~= string.byte('e') then
-    >    window:mvaddstr(30, 60, '')
-    >    print(render_state.history)
-    >    window:getch()
-    >    render_state.history:insert({first_zettel=view_settings.first_zettel, current_zettel_id=current_zettel_id})
-    >  end
-    >  -- move along the graph
-    >  if key == string.byte('j') then
-    >    -- child or next sibling
-    >    if curr.child then
-    >      current_zettel_id = curr.child
-    >    elseif curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('k') then
-    >    -- parent or previous sibling
-    >    if curr.parent then
-    >      current_zettel_id = curr.parent
-    >    elseif curr.prev then
-    >      current_zettel_id = curr.prev
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('h') then
-    >    -- previous sibling or parent
-    >    if curr.prev then
-    >      current_zettel_id = curr.prev
-    >    elseif curr.parent then
-    >      current_zettel_id = curr.parent
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('l') then
-    >    -- next sibling or next sibling of parent
-    >    if curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  -- move along the screen
-    >  elseif key == curses.KEY_UP then
-    >    if render_state.curr_h > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h - 1]
-    >    end
-    >  elseif key == curses.KEY_DOWN then
-    >    if render_state.wh2id[render_state.curr_w][render_state.curr_h + 1] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h + 1]
-    >    end
-    >  elseif key == curses.KEY_LEFT then
-    >    if render_state.curr_w > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w - 1][render_state.curr_h]
-    >    end
-    >  elseif key == curses.KEY_RIGHT then
-    >    if render_state.wh2id[render_state.curr_w + 1] and render_state.wh2id[render_state.curr_w + 1][render_state.curr_h] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w + 1][render_state.curr_h]
-    >    end
-    >  -- mutations
-    >  elseif key == string.byte('e') then
-    >    editz(window)
-    >  elseif key == string.byte('a') then
-    >    -- insert sibling after
-    >    local old = curr.next
-    >    curr.next = new_id()
-    >    local new = zettels[curr.next]
-    >    new.data = ''
-    >    new.next = old
-    >    new.prev = current_zettel_id
-    >    if old then
-    >      zettels[old].prev = curr.next
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.next
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('b') then
-    >    -- insert sibling before
-    >    local old = curr.prev
-    >    curr.prev = new_id()
-    >    local new = zettels[curr.prev]
-    >    new.data = ''
-    >    new.prev = old
-    >    new.next = current_zettel_id
-    >    if old then
-    >      zettels[old].next = curr.prev
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.prev
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('c') then
-    >    -- insert child
-    >    local old = curr.child
-    >    curr.child = new_id()
-    >    local new = zettels[curr.child]
-    >    new.data = ''
-    >    new.next = old
-    >    if old then
-    >      assert(zettels[old].prev == nil, "first child shouldn't have a previous sibling")
-    >      zettels[old].prev = curr.child
-    >    end
-    >    new.parent = current_zettel_id
-    >    current_zettel_id = curr.child
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  -- cross-links
-    >  elseif key == string.byte('s') then
-    >    -- save zettel to a stash
-    >    stash = current_zettel_id
-    >  elseif key == string.byte('t') then
-    >    -- cross-link a zettel bidirectionally with what's on the stash
-    >    local insert_crosslink =
-    >      function(a, rel, b_id)
-    >        if a.crosslinks == nil then
-    >          a.crosslinks = {}
-    >        end
-    >        a.crosslinks[rel] = b_id
-    >      end
-    >    insert_crosslink(curr, 'a', stash)
-    >    insert_crosslink(zettels[stash], 'a', current_zettel_id)
-    >    stash = nil
-    >  -- view settings
-    >  elseif key == string.byte('x') then
-    >    if view_settings.width > 5 then
-    >      view_settings.width = view_settings.width - 5
-    >    end
-    >  elseif key == string.byte('X') then
-    >    if view_settings.width < w-5 then
-    >      view_settings.width = view_settings.width + 5
-    >    end
-    >  elseif key == string.byte('y') then
-    >    if view_settings.height > 0 then
-    >      view_settings.height = view_settings.height - 1
-    >    end
-    >  elseif key == string.byte('Y') then
-    >    if view_settings.height < h-2 then
-    >      view_settings.height = view_settings.height + 1
-    >    end
-    >  elseif key == string.byte('z') then
-    >    -- scroll to show the current zettel at top of screen
-    >    -- often has the effect of zooming in on its hierarchy
-    >    view_settings.first_zettel = current_zettel_id
-    >  end
-    >end
-- __teliva_timestamp:
-    >Sat Feb 12 17:49:34 2022
-  update:
-    >function update(window)
-    >  local key = window:getch()
-    >  local h, w = window:getmaxyx()
-    >  local curr = zettels[current_zettel_id]
-    >  assert(curr, string.format('cursor fell off the edge of the world: %s', type(current_zettel_id)))
-    >  -- read from or write to render_state.history
-    >  if key == string.byte('<') then
-    >    -- previous zettel moved to
-    >    -- does NOT undo mutations
-    >    if #render_state.history > 0 then
-    >      view_settings.first_zettel = render_state.history[-1].first_zettel
-    >      current_zettel_id = render_state.history[-1].current_zettel_id
-    >      render_state.history:remove()
-    >    end
-    >    return
-    >  end
-    >  if key ~= string.byte('e') then
-    >    window:mvaddstr(30, 60, '')
-    >    print(render_state.history)
-    >    window:getch()
-    >    local history = render_state.history
-    >    history:insert({first_zettel=view_settings.first_zettel, current_zettel_id=current_zettel_id})
-    >  end
-    >  -- move along the graph
-    >  if key == string.byte('j') then
-    >    -- child or next sibling
-    >    if curr.child then
-    >      current_zettel_id = curr.child
-    >    elseif curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('k') then
-    >    -- parent or previous sibling
-    >    if curr.parent then
-    >      current_zettel_id = curr.parent
-    >    elseif curr.prev then
-    >      current_zettel_id = curr.prev
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('h') then
-    >    -- previous sibling or parent
-    >    if curr.prev then
-    >      current_zettel_id = curr.prev
-    >    elseif curr.parent then
-    >      current_zettel_id = curr.parent
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('l') then
-    >    -- next sibling or next sibling of parent
-    >    if curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  -- move along the screen
-    >  elseif key == curses.KEY_UP then
-    >    if render_state.curr_h > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h - 1]
-    >    end
-    >  elseif key == curses.KEY_DOWN then
-    >    if render_state.wh2id[render_state.curr_w][render_state.curr_h + 1] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h + 1]
-    >    end
-    >  elseif key == curses.KEY_LEFT then
-    >    if render_state.curr_w > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w - 1][render_state.curr_h]
-    >    end
-    >  elseif key == curses.KEY_RIGHT then
-    >    if render_state.wh2id[render_state.curr_w + 1] and render_state.wh2id[render_state.curr_w + 1][render_state.curr_h] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w + 1][render_state.curr_h]
-    >    end
-    >  -- mutations
-    >  elseif key == string.byte('e') then
-    >    editz(window)
-    >  elseif key == string.byte('a') then
-    >    -- insert sibling after
-    >    local old = curr.next
-    >    curr.next = new_id()
-    >    local new = zettels[curr.next]
-    >    new.data = ''
-    >    new.next = old
-    >    new.prev = current_zettel_id
-    >    if old then
-    >      zettels[old].prev = curr.next
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.next
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('b') then
-    >    -- insert sibling before
-    >    local old = curr.prev
-    >    curr.prev = new_id()
-    >    local new = zettels[curr.prev]
-    >    new.data = ''
-    >    new.prev = old
-    >    new.next = current_zettel_id
-    >    if old then
-    >      zettels[old].next = curr.prev
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.prev
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('c') then
-    >    -- insert child
-    >    local old = curr.child
-    >    curr.child = new_id()
-    >    local new = zettels[curr.child]
-    >    new.data = ''
-    >    new.next = old
-    >    if old then
-    >      assert(zettels[old].prev == nil, "first child shouldn't have a previous sibling")
-    >      zettels[old].prev = curr.child
-    >    end
-    >    new.parent = current_zettel_id
-    >    current_zettel_id = curr.child
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  -- cross-links
-    >  elseif key == string.byte('s') then
-    >    -- save zettel to a stash
-    >    stash = current_zettel_id
-    >  elseif key == string.byte('t') then
-    >    -- cross-link a zettel bidirectionally with what's on the stash
-    >    local insert_crosslink =
-    >      function(a, rel, b_id)
-    >        if a.crosslinks == nil then
-    >          a.crosslinks = {}
-    >        end
-    >        a.crosslinks[rel] = b_id
-    >      end
-    >    insert_crosslink(curr, 'a', stash)
-    >    insert_crosslink(zettels[stash], 'a', current_zettel_id)
-    >    stash = nil
-    >  -- view settings
-    >  elseif key == string.byte('x') then
-    >    if view_settings.width > 5 then
-    >      view_settings.width = view_settings.width - 5
-    >    end
-    >  elseif key == string.byte('X') then
-    >    if view_settings.width < w-5 then
-    >      view_settings.width = view_settings.width + 5
-    >    end
-    >  elseif key == string.byte('y') then
-    >    if view_settings.height > 0 then
-    >      view_settings.height = view_settings.height - 1
-    >    end
-    >  elseif key == string.byte('Y') then
-    >    if view_settings.height < h-2 then
-    >      view_settings.height = view_settings.height + 1
-    >    end
-    >  elseif key == string.byte('z') then
-    >    -- scroll to show the current zettel at top of screen
-    >    -- often has the effect of zooming in on its hierarchy
-    >    view_settings.first_zettel = current_zettel_id
-    >  end
-    >end
-- __teliva_timestamp:
-    >Sat Feb 12 17:50:49 2022
-  update:
-    >function update(window)
-    >  local key = window:getch()
-    >  local h, w = window:getmaxyx()
-    >  local curr = zettels[current_zettel_id]
-    >  assert(curr, string.format('cursor fell off the edge of the world: %s', type(current_zettel_id)))
-    >  -- read from or write to render_state.history
-    >  if key == string.byte('<') then
-    >    -- previous zettel moved to
-    >    -- does NOT undo mutations
-    >    if #render_state.history > 0 then
-    >      view_settings.first_zettel = render_state.history[-1].first_zettel
-    >      current_zettel_id = render_state.history[-1].current_zettel_id
-    >      table.remove(render_state.history)
-    >    end
-    >    return
-    >  end
-    >  if key ~= string.byte('e') then
-    >    table.insert(render_state.history, {first_zettel=view_settings.first_zettel, current_zettel_id=current_zettel_id})
-    >  end
-    >  -- move along the graph
-    >  if key == string.byte('j') then
-    >    -- child or next sibling
-    >    if curr.child then
-    >      current_zettel_id = curr.child
-    >    elseif curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('k') then
-    >    -- parent or previous sibling
-    >    if curr.parent then
-    >      current_zettel_id = curr.parent
-    >    elseif curr.prev then
-    >      current_zettel_id = curr.prev
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('h') then
-    >    -- previous sibling or parent
-    >    if curr.prev then
-    >      current_zettel_id = curr.prev
-    >    elseif curr.parent then
-    >      current_zettel_id = curr.parent
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('l') then
-    >    -- next sibling or next sibling of parent
-    >    if curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  -- move along the screen
-    >  elseif key == curses.KEY_UP then
-    >    if render_state.curr_h > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h - 1]
-    >    end
-    >  elseif key == curses.KEY_DOWN then
-    >    if render_state.wh2id[render_state.curr_w][render_state.curr_h + 1] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h + 1]
-    >    end
-    >  elseif key == curses.KEY_LEFT then
-    >    if render_state.curr_w > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w - 1][render_state.curr_h]
-    >    end
-    >  elseif key == curses.KEY_RIGHT then
-    >    if render_state.wh2id[render_state.curr_w + 1] and render_state.wh2id[render_state.curr_w + 1][render_state.curr_h] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w + 1][render_state.curr_h]
-    >    end
-    >  -- mutations
-    >  elseif key == string.byte('e') then
-    >    editz(window)
-    >  elseif key == string.byte('a') then
-    >    -- insert sibling after
-    >    local old = curr.next
-    >    curr.next = new_id()
-    >    local new = zettels[curr.next]
-    >    new.data = ''
-    >    new.next = old
-    >    new.prev = current_zettel_id
-    >    if old then
-    >      zettels[old].prev = curr.next
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.next
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('b') then
-    >    -- insert sibling before
-    >    local old = curr.prev
-    >    curr.prev = new_id()
-    >    local new = zettels[curr.prev]
-    >    new.data = ''
-    >    new.prev = old
-    >    new.next = current_zettel_id
-    >    if old then
-    >      zettels[old].next = curr.prev
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.prev
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('c') then
-    >    -- insert child
-    >    local old = curr.child
-    >    curr.child = new_id()
-    >    local new = zettels[curr.child]
-    >    new.data = ''
-    >    new.next = old
-    >    if old then
-    >      assert(zettels[old].prev == nil, "first child shouldn't have a previous sibling")
-    >      zettels[old].prev = curr.child
-    >    end
-    >    new.parent = current_zettel_id
-    >    current_zettel_id = curr.child
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  -- cross-links
-    >  elseif key == string.byte('s') then
-    >    -- save zettel to a stash
-    >    stash = current_zettel_id
-    >  elseif key == string.byte('t') then
-    >    -- cross-link a zettel bidirectionally with what's on the stash
-    >    local insert_crosslink =
-    >      function(a, rel, b_id)
-    >        if a.crosslinks == nil then
-    >          a.crosslinks = {}
-    >        end
-    >        a.crosslinks[rel] = b_id
-    >      end
-    >    insert_crosslink(curr, 'a', stash)
-    >    insert_crosslink(zettels[stash], 'a', current_zettel_id)
-    >    stash = nil
-    >  -- view settings
-    >  elseif key == string.byte('x') then
-    >    if view_settings.width > 5 then
-    >      view_settings.width = view_settings.width - 5
-    >    end
-    >  elseif key == string.byte('X') then
-    >    if view_settings.width < w-5 then
-    >      view_settings.width = view_settings.width + 5
-    >    end
-    >  elseif key == string.byte('y') then
-    >    if view_settings.height > 0 then
-    >      view_settings.height = view_settings.height - 1
-    >    end
-    >  elseif key == string.byte('Y') then
-    >    if view_settings.height < h-2 then
-    >      view_settings.height = view_settings.height + 1
-    >    end
-    >  elseif key == string.byte('z') then
-    >    -- scroll to show the current zettel at top of screen
-    >    -- often has the effect of zooming in on its hierarchy
-    >    view_settings.first_zettel = current_zettel_id
-    >  end
-    >end
-- __teliva_timestamp:
-    >Sat Feb 12 17:52:42 2022
-  update:
-    >function update(window)
-    >  local key = window:getch()
-    >  local h, w = window:getmaxyx()
-    >  local curr = zettels[current_zettel_id]
-    >  assert(curr, string.format('cursor fell off the edge of the world: %s', type(current_zettel_id)))
-    >  -- read from or write to render_state.history
-    >  if key == string.byte('<') then
-    >    -- previous zettel moved to
-    >    -- does NOT undo mutations
-    >    if #render_state.history > 0 then
-    >      local previous_state = render_state.history[-1]
-    >      window:mvaddstr(30, 60, '')
-    >      print(previous_state)
-    >      window:getch()
-    >      view_settings.first_zettel = previous_state.first_zettel
-    >      current_zettel_id = render_state.history[-1].current_zettel_id
-    >      table.remove(render_state.history)
-    >    end
-    >    return
-    >  end
-    >  if key ~= string.byte('e') then
-    >    table.insert(render_state.history, {first_zettel=view_settings.first_zettel, current_zettel_id=current_zettel_id})
-    >  end
-    >  -- move along the graph
-    >  if key == string.byte('j') then
-    >    -- child or next sibling
-    >    if curr.child then
-    >      current_zettel_id = curr.child
-    >    elseif curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('k') then
-    >    -- parent or previous sibling
-    >    if curr.parent then
-    >      current_zettel_id = curr.parent
-    >    elseif curr.prev then
-    >      current_zettel_id = curr.prev
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('h') then
-    >    -- previous sibling or parent
-    >    if curr.prev then
-    >      current_zettel_id = curr.prev
-    >    elseif curr.parent then
-    >      current_zettel_id = curr.parent
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('l') then
-    >    -- next sibling or next sibling of parent
-    >    if curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  -- move along the screen
-    >  elseif key == curses.KEY_UP then
-    >    if render_state.curr_h > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h - 1]
-    >    end
-    >  elseif key == curses.KEY_DOWN then
-    >    if render_state.wh2id[render_state.curr_w][render_state.curr_h + 1] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h + 1]
-    >    end
-    >  elseif key == curses.KEY_LEFT then
-    >    if render_state.curr_w > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w - 1][render_state.curr_h]
-    >    end
-    >  elseif key == curses.KEY_RIGHT then
-    >    if render_state.wh2id[render_state.curr_w + 1] and render_state.wh2id[render_state.curr_w + 1][render_state.curr_h] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w + 1][render_state.curr_h]
-    >    end
-    >  -- mutations
-    >  elseif key == string.byte('e') then
-    >    editz(window)
-    >  elseif key == string.byte('a') then
-    >    -- insert sibling after
-    >    local old = curr.next
-    >    curr.next = new_id()
-    >    local new = zettels[curr.next]
-    >    new.data = ''
-    >    new.next = old
-    >    new.prev = current_zettel_id
-    >    if old then
-    >      zettels[old].prev = curr.next
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.next
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('b') then
-    >    -- insert sibling before
-    >    local old = curr.prev
-    >    curr.prev = new_id()
-    >    local new = zettels[curr.prev]
-    >    new.data = ''
-    >    new.prev = old
-    >    new.next = current_zettel_id
-    >    if old then
-    >      zettels[old].next = curr.prev
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.prev
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('c') then
-    >    -- insert child
-    >    local old = curr.child
-    >    curr.child = new_id()
-    >    local new = zettels[curr.child]
-    >    new.data = ''
-    >    new.next = old
-    >    if old then
-    >      assert(zettels[old].prev == nil, "first child shouldn't have a previous sibling")
-    >      zettels[old].prev = curr.child
-    >    end
-    >    new.parent = current_zettel_id
-    >    current_zettel_id = curr.child
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  -- cross-links
-    >  elseif key == string.byte('s') then
-    >    -- save zettel to a stash
-    >    stash = current_zettel_id
-    >  elseif key == string.byte('t') then
-    >    -- cross-link a zettel bidirectionally with what's on the stash
-    >    local insert_crosslink =
-    >      function(a, rel, b_id)
-    >        if a.crosslinks == nil then
-    >          a.crosslinks = {}
-    >        end
-    >        a.crosslinks[rel] = b_id
-    >      end
-    >    insert_crosslink(curr, 'a', stash)
-    >    insert_crosslink(zettels[stash], 'a', current_zettel_id)
-    >    stash = nil
-    >  -- view settings
-    >  elseif key == string.byte('x') then
-    >    if view_settings.width > 5 then
-    >      view_settings.width = view_settings.width - 5
-    >    end
-    >  elseif key == string.byte('X') then
-    >    if view_settings.width < w-5 then
-    >      view_settings.width = view_settings.width + 5
-    >    end
-    >  elseif key == string.byte('y') then
-    >    if view_settings.height > 0 then
-    >      view_settings.height = view_settings.height - 1
-    >    end
-    >  elseif key == string.byte('Y') then
-    >    if view_settings.height < h-2 then
-    >      view_settings.height = view_settings.height + 1
-    >    end
-    >  elseif key == string.byte('z') then
-    >    -- scroll to show the current zettel at top of screen
-    >    -- often has the effect of zooming in on its hierarchy
-    >    view_settings.first_zettel = current_zettel_id
-    >  end
-    >end
-- __teliva_timestamp:
-    >Sat Feb 12 17:54:43 2022
-  update:
-    >function update(window)
-    >  local key = window:getch()
-    >  local h, w = window:getmaxyx()
-    >  local curr = zettels[current_zettel_id]
-    >  assert(curr, string.format('cursor fell off the edge of the world: %s', type(current_zettel_id)))
-    >  -- read from or write to render_state.history
-    >  if key == string.byte('<') then
-    >    -- previous zettel moved to
-    >    -- does NOT undo mutations
-    >    if #render_state.history > 0 then
-    >      window:mvaddstr(30, 60, '')
-    >      print(#render_state.history)
-    >      local previous_state = render_state.history[-1]
-    >      print(previous_state)
-    >      window:getch()
-    >      view_settings.first_zettel = previous_state.first_zettel
-    >      current_zettel_id = render_state.history[-1].current_zettel_id
-    >      table.remove(render_state.history)
-    >    end
-    >    return
-    >  end
-    >  if key ~= string.byte('e') then
-    >    table.insert(render_state.history, {first_zettel=view_settings.first_zettel, current_zettel_id=current_zettel_id})
-    >  end
-    >  -- move along the graph
-    >  if key == string.byte('j') then
-    >    -- child or next sibling
-    >    if curr.child then
-    >      current_zettel_id = curr.child
-    >    elseif curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('k') then
-    >    -- parent or previous sibling
-    >    if curr.parent then
-    >      current_zettel_id = curr.parent
-    >    elseif curr.prev then
-    >      current_zettel_id = curr.prev
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('h') then
-    >    -- previous sibling or parent
-    >    if curr.prev then
-    >      current_zettel_id = curr.prev
-    >    elseif curr.parent then
-    >      current_zettel_id = curr.parent
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('l') then
-    >    -- next sibling or next sibling of parent
-    >    if curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  -- move along the screen
-    >  elseif key == curses.KEY_UP then
-    >    if render_state.curr_h > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h - 1]
-    >    end
-    >  elseif key == curses.KEY_DOWN then
-    >    if render_state.wh2id[render_state.curr_w][render_state.curr_h + 1] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h + 1]
-    >    end
-    >  elseif key == curses.KEY_LEFT then
-    >    if render_state.curr_w > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w - 1][render_state.curr_h]
-    >    end
-    >  elseif key == curses.KEY_RIGHT then
-    >    if render_state.wh2id[render_state.curr_w + 1] and render_state.wh2id[render_state.curr_w + 1][render_state.curr_h] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w + 1][render_state.curr_h]
-    >    end
-    >  -- mutations
-    >  elseif key == string.byte('e') then
-    >    editz(window)
-    >  elseif key == string.byte('a') then
-    >    -- insert sibling after
-    >    local old = curr.next
-    >    curr.next = new_id()
-    >    local new = zettels[curr.next]
-    >    new.data = ''
-    >    new.next = old
-    >    new.prev = current_zettel_id
-    >    if old then
-    >      zettels[old].prev = curr.next
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.next
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('b') then
-    >    -- insert sibling before
-    >    local old = curr.prev
-    >    curr.prev = new_id()
-    >    local new = zettels[curr.prev]
-    >    new.data = ''
-    >    new.prev = old
-    >    new.next = current_zettel_id
-    >    if old then
-    >      zettels[old].next = curr.prev
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.prev
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('c') then
-    >    -- insert child
-    >    local old = curr.child
-    >    curr.child = new_id()
-    >    local new = zettels[curr.child]
-    >    new.data = ''
-    >    new.next = old
-    >    if old then
-    >      assert(zettels[old].prev == nil, "first child shouldn't have a previous sibling")
-    >      zettels[old].prev = curr.child
-    >    end
-    >    new.parent = current_zettel_id
-    >    current_zettel_id = curr.child
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  -- cross-links
-    >  elseif key == string.byte('s') then
-    >    -- save zettel to a stash
-    >    stash = current_zettel_id
-    >  elseif key == string.byte('t') then
-    >    -- cross-link a zettel bidirectionally with what's on the stash
-    >    local insert_crosslink =
-    >      function(a, rel, b_id)
-    >        if a.crosslinks == nil then
-    >          a.crosslinks = {}
-    >        end
-    >        a.crosslinks[rel] = b_id
-    >      end
-    >    insert_crosslink(curr, 'a', stash)
-    >    insert_crosslink(zettels[stash], 'a', current_zettel_id)
-    >    stash = nil
-    >  -- view settings
-    >  elseif key == string.byte('x') then
-    >    if view_settings.width > 5 then
-    >      view_settings.width = view_settings.width - 5
-    >    end
-    >  elseif key == string.byte('X') then
-    >    if view_settings.width < w-5 then
-    >      view_settings.width = view_settings.width + 5
-    >    end
-    >  elseif key == string.byte('y') then
-    >    if view_settings.height > 0 then
-    >      view_settings.height = view_settings.height - 1
-    >    end
-    >  elseif key == string.byte('Y') then
-    >    if view_settings.height < h-2 then
-    >      view_settings.height = view_settings.height + 1
-    >    end
-    >  elseif key == string.byte('z') then
-    >    -- scroll to show the current zettel at top of screen
-    >    -- often has the effect of zooming in on its hierarchy
-    >    view_settings.first_zettel = current_zettel_id
-    >  end
-    >end
-- __teliva_timestamp:
-    >Sat Feb 12 17:55:42 2022
-  update:
-    >function update(window)
-    >  local key = window:getch()
-    >  local h, w = window:getmaxyx()
-    >  local curr = zettels[current_zettel_id]
-    >  assert(curr, string.format('cursor fell off the edge of the world: %s', type(current_zettel_id)))
-    >  -- read from or write to render_state.history
-    >  if key == string.byte('<') then
-    >    -- previous zettel moved to
-    >    -- does NOT undo mutations
-    >    if #render_state.history > 0 then
-    >      local previous_state = render_state.history[#render_state.history]
-    >      view_settings.first_zettel = previous_state.first_zettel
-    >      current_zettel_id = render_state.history[-1].current_zettel_id
-    >      table.remove(render_state.history)
-    >    end
-    >    return
-    >  end
-    >  if key ~= string.byte('e') then
-    >    table.insert(render_state.history, {first_zettel=view_settings.first_zettel, current_zettel_id=current_zettel_id})
-    >  end
-    >  -- move along the graph
-    >  if key == string.byte('j') then
-    >    -- child or next sibling
-    >    if curr.child then
-    >      current_zettel_id = curr.child
-    >    elseif curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('k') then
-    >    -- parent or previous sibling
-    >    if curr.parent then
-    >      current_zettel_id = curr.parent
-    >    elseif curr.prev then
-    >      current_zettel_id = curr.prev
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('h') then
-    >    -- previous sibling or parent
-    >    if curr.prev then
-    >      current_zettel_id = curr.prev
-    >    elseif curr.parent then
-    >      current_zettel_id = curr.parent
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('l') then
-    >    -- next sibling or next sibling of parent
-    >    if curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  -- move along the screen
-    >  elseif key == curses.KEY_UP then
-    >    if render_state.curr_h > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h - 1]
-    >    end
-    >  elseif key == curses.KEY_DOWN then
-    >    if render_state.wh2id[render_state.curr_w][render_state.curr_h + 1] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h + 1]
-    >    end
-    >  elseif key == curses.KEY_LEFT then
-    >    if render_state.curr_w > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w - 1][render_state.curr_h]
-    >    end
-    >  elseif key == curses.KEY_RIGHT then
-    >    if render_state.wh2id[render_state.curr_w + 1] and render_state.wh2id[render_state.curr_w + 1][render_state.curr_h] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w + 1][render_state.curr_h]
-    >    end
-    >  -- mutations
-    >  elseif key == string.byte('e') then
-    >    editz(window)
-    >  elseif key == string.byte('a') then
-    >    -- insert sibling after
-    >    local old = curr.next
-    >    curr.next = new_id()
-    >    local new = zettels[curr.next]
-    >    new.data = ''
-    >    new.next = old
-    >    new.prev = current_zettel_id
-    >    if old then
-    >      zettels[old].prev = curr.next
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.next
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('b') then
-    >    -- insert sibling before
-    >    local old = curr.prev
-    >    curr.prev = new_id()
-    >    local new = zettels[curr.prev]
-    >    new.data = ''
-    >    new.prev = old
-    >    new.next = current_zettel_id
-    >    if old then
-    >      zettels[old].next = curr.prev
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.prev
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('c') then
-    >    -- insert child
-    >    local old = curr.child
-    >    curr.child = new_id()
-    >    local new = zettels[curr.child]
-    >    new.data = ''
-    >    new.next = old
-    >    if old then
-    >      assert(zettels[old].prev == nil, "first child shouldn't have a previous sibling")
-    >      zettels[old].prev = curr.child
-    >    end
-    >    new.parent = current_zettel_id
-    >    current_zettel_id = curr.child
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  -- cross-links
-    >  elseif key == string.byte('s') then
-    >    -- save zettel to a stash
-    >    stash = current_zettel_id
-    >  elseif key == string.byte('t') then
-    >    -- cross-link a zettel bidirectionally with what's on the stash
-    >    local insert_crosslink =
-    >      function(a, rel, b_id)
-    >        if a.crosslinks == nil then
-    >          a.crosslinks = {}
-    >        end
-    >        a.crosslinks[rel] = b_id
-    >      end
-    >    insert_crosslink(curr, 'a', stash)
-    >    insert_crosslink(zettels[stash], 'a', current_zettel_id)
-    >    stash = nil
-    >  -- view settings
-    >  elseif key == string.byte('x') then
-    >    if view_settings.width > 5 then
-    >      view_settings.width = view_settings.width - 5
-    >    end
-    >  elseif key == string.byte('X') then
-    >    if view_settings.width < w-5 then
-    >      view_settings.width = view_settings.width + 5
-    >    end
-    >  elseif key == string.byte('y') then
-    >    if view_settings.height > 0 then
-    >      view_settings.height = view_settings.height - 1
-    >    end
-    >  elseif key == string.byte('Y') then
-    >    if view_settings.height < h-2 then
-    >      view_settings.height = view_settings.height + 1
-    >    end
-    >  elseif key == string.byte('z') then
-    >    -- scroll to show the current zettel at top of screen
-    >    -- often has the effect of zooming in on its hierarchy
-    >    view_settings.first_zettel = current_zettel_id
-    >  end
-    >end
-- __teliva_timestamp:
-    >Sat Feb 12 17:56:13 2022
-  update:
-    >function update(window)
-    >  local key = window:getch()
-    >  local h, w = window:getmaxyx()
-    >  local curr = zettels[current_zettel_id]
-    >  assert(curr, string.format('cursor fell off the edge of the world: %s', type(current_zettel_id)))
-    >  -- read from or write to render_state.history
-    >  if key == string.byte('<') then
-    >    -- previous zettel moved to
-    >    -- does NOT undo mutations
-    >    if #render_state.history > 0 then
-    >      print(render_state.history[1])
-    >      window:getch()
-    >      local previous_state = render_state.history[#render_state.history]
-    >      view_settings.first_zettel = previous_state.first_zettel
-    >      current_zettel_id = render_state.history[-1].current_zettel_id
-    >      table.remove(render_state.history)
-    >    end
-    >    return
-    >  end
-    >  if key ~= string.byte('e') then
-    >    table.insert(render_state.history, {first_zettel=view_settings.first_zettel, current_zettel_id=current_zettel_id})
-    >  end
-    >  -- move along the graph
-    >  if key == string.byte('j') then
-    >    -- child or next sibling
-    >    if curr.child then
-    >      current_zettel_id = curr.child
-    >    elseif curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('k') then
-    >    -- parent or previous sibling
-    >    if curr.parent then
-    >      current_zettel_id = curr.parent
-    >    elseif curr.prev then
-    >      current_zettel_id = curr.prev
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('h') then
-    >    -- previous sibling or parent
-    >    if curr.prev then
-    >      current_zettel_id = curr.prev
-    >    elseif curr.parent then
-    >      current_zettel_id = curr.parent
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('l') then
-    >    -- next sibling or next sibling of parent
-    >    if curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  -- move along the screen
-    >  elseif key == curses.KEY_UP then
-    >    if render_state.curr_h > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h - 1]
-    >    end
-    >  elseif key == curses.KEY_DOWN then
-    >    if render_state.wh2id[render_state.curr_w][render_state.curr_h + 1] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h + 1]
-    >    end
-    >  elseif key == curses.KEY_LEFT then
-    >    if render_state.curr_w > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w - 1][render_state.curr_h]
-    >    end
-    >  elseif key == curses.KEY_RIGHT then
-    >    if render_state.wh2id[render_state.curr_w + 1] and render_state.wh2id[render_state.curr_w + 1][render_state.curr_h] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w + 1][render_state.curr_h]
-    >    end
-    >  -- mutations
-    >  elseif key == string.byte('e') then
-    >    editz(window)
-    >  elseif key == string.byte('a') then
-    >    -- insert sibling after
-    >    local old = curr.next
-    >    curr.next = new_id()
-    >    local new = zettels[curr.next]
-    >    new.data = ''
-    >    new.next = old
-    >    new.prev = current_zettel_id
-    >    if old then
-    >      zettels[old].prev = curr.next
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.next
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('b') then
-    >    -- insert sibling before
-    >    local old = curr.prev
-    >    curr.prev = new_id()
-    >    local new = zettels[curr.prev]
-    >    new.data = ''
-    >    new.prev = old
-    >    new.next = current_zettel_id
-    >    if old then
-    >      zettels[old].next = curr.prev
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.prev
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('c') then
-    >    -- insert child
-    >    local old = curr.child
-    >    curr.child = new_id()
-    >    local new = zettels[curr.child]
-    >    new.data = ''
-    >    new.next = old
-    >    if old then
-    >      assert(zettels[old].prev == nil, "first child shouldn't have a previous sibling")
-    >      zettels[old].prev = curr.child
-    >    end
-    >    new.parent = current_zettel_id
-    >    current_zettel_id = curr.child
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  -- cross-links
-    >  elseif key == string.byte('s') then
-    >    -- save zettel to a stash
-    >    stash = current_zettel_id
-    >  elseif key == string.byte('t') then
-    >    -- cross-link a zettel bidirectionally with what's on the stash
-    >    local insert_crosslink =
-    >      function(a, rel, b_id)
-    >        if a.crosslinks == nil then
-    >          a.crosslinks = {}
-    >        end
-    >        a.crosslinks[rel] = b_id
-    >      end
-    >    insert_crosslink(curr, 'a', stash)
-    >    insert_crosslink(zettels[stash], 'a', current_zettel_id)
-    >    stash = nil
-    >  -- view settings
-    >  elseif key == string.byte('x') then
-    >    if view_settings.width > 5 then
-    >      view_settings.width = view_settings.width - 5
-    >    end
-    >  elseif key == string.byte('X') then
-    >    if view_settings.width < w-5 then
-    >      view_settings.width = view_settings.width + 5
-    >    end
-    >  elseif key == string.byte('y') then
-    >    if view_settings.height > 0 then
-    >      view_settings.height = view_settings.height - 1
-    >    end
-    >  elseif key == string.byte('Y') then
-    >    if view_settings.height < h-2 then
-    >      view_settings.height = view_settings.height + 1
-    >    end
-    >  elseif key == string.byte('z') then
-    >    -- scroll to show the current zettel at top of screen
-    >    -- often has the effect of zooming in on its hierarchy
-    >    view_settings.first_zettel = current_zettel_id
-    >  end
-    >end
-- __teliva_timestamp:
-    >Sat Feb 12 17:56:25 2022
-  update:
-    >function update(window)
-    >  local key = window:getch()
-    >  local h, w = window:getmaxyx()
-    >  local curr = zettels[current_zettel_id]
-    >  assert(curr, string.format('cursor fell off the edge of the world: %s', type(current_zettel_id)))
-    >  -- read from or write to render_state.history
-    >  if key == string.byte('<') then
-    >    -- previous zettel moved to
-    >    -- does NOT undo mutations
-    >    if #render_state.history > 0 then
-    >      window:mvaddstr(30, 60, '')
-    >      print(render_state.history[1])
-    >      window:getch()
-    >      local previous_state = render_state.history[#render_state.history]
-    >      view_settings.first_zettel = previous_state.first_zettel
-    >      current_zettel_id = render_state.history[-1].current_zettel_id
-    >      table.remove(render_state.history)
-    >    end
-    >    return
-    >  end
-    >  if key ~= string.byte('e') then
-    >    table.insert(render_state.history, {first_zettel=view_settings.first_zettel, current_zettel_id=current_zettel_id})
-    >  end
-    >  -- move along the graph
-    >  if key == string.byte('j') then
-    >    -- child or next sibling
-    >    if curr.child then
-    >      current_zettel_id = curr.child
-    >    elseif curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('k') then
-    >    -- parent or previous sibling
-    >    if curr.parent then
-    >      current_zettel_id = curr.parent
-    >    elseif curr.prev then
-    >      current_zettel_id = curr.prev
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('h') then
-    >    -- previous sibling or parent
-    >    if curr.prev then
-    >      current_zettel_id = curr.prev
-    >    elseif curr.parent then
-    >      current_zettel_id = curr.parent
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  elseif key == string.byte('l') then
-    >    -- next sibling or next sibling of parent
-    >    if curr.next then
-    >      current_zettel_id = curr.next
-    >    elseif curr.parent and zettels[curr.parent].next then
-    >      current_zettel_id = zettels[curr.parent].next
-    >    end
-    >    -- scroll if necessary
-    >    if not render_state.displayed[current_zettel_id] then
-    >      view_settings.first_zettel = current_zettel_id
-    >    end
-    >  -- move along the screen
-    >  elseif key == curses.KEY_UP then
-    >    if render_state.curr_h > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h - 1]
-    >    end
-    >  elseif key == curses.KEY_DOWN then
-    >    if render_state.wh2id[render_state.curr_w][render_state.curr_h + 1] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w][render_state.curr_h + 1]
-    >    end
-    >  elseif key == curses.KEY_LEFT then
-    >    if render_state.curr_w > 1 then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w - 1][render_state.curr_h]
-    >    end
-    >  elseif key == curses.KEY_RIGHT then
-    >    if render_state.wh2id[render_state.curr_w + 1] and render_state.wh2id[render_state.curr_w + 1][render_state.curr_h] then
-    >      current_zettel_id = render_state.wh2id[render_state.curr_w + 1][render_state.curr_h]
-    >    end
-    >  -- mutations
-    >  elseif key == string.byte('e') then
-    >    editz(window)
-    >  elseif key == string.byte('a') then
-    >    -- insert sibling after
-    >    local old = curr.next
-    >    curr.next = new_id()
-    >    local new = zettels[curr.next]
-    >    new.data = ''
-    >    new.next = old
-    >    new.prev = current_zettel_id
-    >    if old then
-    >      zettels[old].prev = curr.next
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.next
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('b') then
-    >    -- insert sibling before
-    >    local old = curr.prev
-    >    curr.prev = new_id()
-    >    local new = zettels[curr.prev]
-    >    new.data = ''
-    >    new.prev = old
-    >    new.next = current_zettel_id
-    >    if old then
-    >      zettels[old].next = curr.prev
-    >      assert(curr.parent == zettels[old].parent, 'siblings should have same parent')
-    >    end
-    >    new.parent = curr.parent
-    >    current_zettel_id = curr.prev
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  elseif key == string.byte('c') then
-    >    -- insert child
-    >    local old = curr.child
-    >    curr.child = new_id()
-    >    local new = zettels[curr.child]
-    >    new.data = ''
-    >    new.next = old
-    >    if old then
-    >      assert(zettels[old].prev == nil, "first child shouldn't have a previous sibling")
-    >      zettels[old].prev = curr.child
-    >    end
-    >    new.parent = current_zettel_id
-    >    current_zettel_id = curr.child
-    >    render(window) -- recompute render_state
-    >    editz(window)
-    >  -- cross-links
-    >  elseif key == string.byte('s') then
-    >    -- save zettel to a stash
-    >    stash = current_zettel_id
-    >  elseif key == string.byte('t') then
-    >    -- cross-link a zettel bidirectionally with what's on the stash
-    >    local insert_crosslink =
-    >      function(a, rel, b_id)
-    >        if a.crosslinks == nil then
-    >          a.crosslinks = {}
-    >        end
-    >        a.crosslinks[rel] = b_id
-    >      end
-    >    insert_crosslink(curr, 'a', stash)
-    >    insert_crosslink(zettels[stash], 'a', current_zettel_id)
-    >    stash = nil
-    >  -- view settings
-    >  elseif key == string.byte('x') then
-    >    if view_settings.width > 5 then
-    >      view_settings.width = view_settings.width - 5
-    >    end
-    >  elseif key == string.byte('X') then
-    >    if view_settings.width < w-5 then
-    >      view_settings.width = view_settings.width + 5
-    >    end
-    >  elseif key == string.byte('y') then
-    >    if view_settings.height > 0 then
-    >      view_settings.height = view_settings.height - 1
-    >    end
-    >  elseif key == string.byte('Y') then
-    >    if view_settings.height < h-2 then
-    >      view_settings.height = view_settings.height + 1
-    >    end
-    >  elseif key == string.byte('z') then
-    >    -- scroll to show the current zettel at top of screen
-    >    -- often has the effect of zooming in on its hierarchy
-    >    view_settings.first_zettel = current_zettel_id
-    >  end
-    >end
 - __teliva_timestamp:
     >Sat Feb 12 17:57:15 2022
   update: