
doc:   [
    DocGroup({"tag": "h1"}, [
        DocChars("aejlo wor"), DocGroup({"tag": "caret", "client": "a"}, []),
        DocChars("!What\'s up with you?")
    ])
]

a_del: [
    DelGroup([
        DelSkip(1), DelChars(5), DelSkip(2), DelChars(1), DelGroup([]),
        DelSkip(20)
    ])
]
a_add: [
    AddGroup({"tag": "h1"}, [
        AddChars("l"), AddGroup({"tag": "caret", "client": "a"}, []),
        AddSkip(1), AddChars(" "), AddSkip(2)
    ]),
    AddGroup({"tag": "bullet"}, [
        AddGroup({"tag": "h3"}, [
            AddSkip(20)
        ])
    ])
]

b_del: [
    DelGroup([
        DelChars(1), DelSkip(1), DelChars(1), DelSkip(27)
    ])
]
b_add: [
    AddGroup({"tag": "bullet"}, [
        AddGroup({"tag": "pre"}, [
            AddChars("A"), AddSkip(1)
        ]),
        AddGroup({"tag": "p"}, [
            AddGroup({"client": "b", "tag": "caret"}, []),
            AddSkip(27)
        ])
    ])
]
