@ ProgramNode (location: (1,0)-(7,6))
├── flags: ∅
├── locals: [:c, :d]
└── statements:
    @ StatementsNode (location: (1,0)-(7,6))
    ├── flags: ∅
    └── body: (length: 2)
        ├── @ LocalVariableWriteNode (location: (1,0)-(1,11))
        │   ├── flags: newline
        │   ├── name: :c
        │   ├── depth: 0
        │   ├── name_loc: (1,0)-(1,1) = "c"
        │   ├── value:
        │   │   @ StringNode (location: (1,4)-(1,11))
        │   │   ├── flags: ∅
        │   │   ├── opening_loc: (1,4)-(1,11) = "<<'CCC'"
        │   │   ├── content_loc: (2,0)-(5,0) = "line2\nline3\nline4\n"
        │   │   ├── closing_loc: (5,0)-(6,0) = "CCC\n"
        │   │   └── unescaped: "line2\nline3\nline4\n"
        │   └── operator_loc: (1,2)-(1,3) = "="
        └── @ LocalVariableWriteNode (location: (7,0)-(7,6))
            ├── flags: newline
            ├── name: :d
            ├── depth: 0
            ├── name_loc: (7,0)-(7,1) = "d"
            ├── value:
            │   @ IntegerNode (location: (7,4)-(7,6))
            │   ├── flags: static_literal, decimal
            │   └── value: 42
            └── operator_loc: (7,2)-(7,3) = "="
