@ ProgramNode (location: (0...56))
├── locals: [:a, :b]
└── statements:
    @ StatementsNode (location: (0...56))
    └── body: (length: 3)
        ├── @ DefinedNode (location: (0...14))
        │   ├── lparen_loc: (8...9) = "("
        │   ├── value:
        │   │   @ InstanceVariableReadNode (location: (9...13))
        │   │   └── name: :@foo
        │   ├── rparen_loc: (13...14) = ")"
        │   └── keyword_loc: (0...8) = "defined?"
        ├── @ DefinedNode (location: (15...28))
        │   ├── lparen_loc: (23...24) = "("
        │   ├── value:
        │   │   @ ConstantReadNode (location: (24...27))
        │   │   └── name: :Foo
        │   ├── rparen_loc: (27...28) = ")"
        │   └── keyword_loc: (15...23) = "defined?"
        └── @ DefinedNode (location: (29...56))
            ├── lparen_loc: (37...38) = "("
            ├── value:
            │   @ ParenthesesNode (location: (38...55))
            │   ├── body:
            │   │   @ StatementsNode (location: (39...54))
            │   │   └── body: (length: 1)
            │   │       └── @ MultiWriteNode (location: (39...54))
            │   │           ├── targets: (length: 2)
            │   │           │   ├── @ LocalVariableTargetNode (location: (40...41))
            │   │           │   │   ├── name: :a
            │   │           │   │   └── depth: 0
            │   │           │   └── @ LocalVariableTargetNode (location: (43...44))
            │   │           │       ├── name: :b
            │   │           │       └── depth: 0
            │   │           ├── lparen_loc: (39...40) = "("
            │   │           ├── rparen_loc: (44...45) = ")"
            │   │           ├── operator_loc: (46...47) = "="
            │   │           └── value:
            │   │               @ ArrayNode (location: (48...54))
            │   │               ├── elements: (length: 2)
            │   │               │   ├── @ IntegerNode (location: (49...50))
            │   │               │   │   └── flags: decimal
            │   │               │   └── @ IntegerNode (location: (52...53))
            │   │               │       └── flags: decimal
            │   │               ├── opening_loc: (48...49) = "["
            │   │               └── closing_loc: (53...54) = "]"
            │   ├── opening_loc: (38...39) = "("
            │   └── closing_loc: (54...55) = ")"
            ├── rparen_loc: (55...56) = ")"
            └── keyword_loc: (29...37) = "defined?"
