▽
└─▣ Attr value: id
  ╙─◈ = "foo"s
    ┠─▣ Attr value: class
    ┃ ╙─◈ ~= "bar"s
    ┃   ┠─◁ #2 [1,1,0] value 3
    ┃   ┖─◁ #3 [0,2,0] value 4
    ┠─◁ #0 [1,0,0] value 1
    ┖─◁ #1 [0,1,0] value 2