@ ProgramNode (location: (1,0)-(1,8))
├── locals: [:a]
└── statements:
    @ StatementsNode (location: (1,0)-(1,8))
    └── body: (length: 1)
        └── @ MultiWriteNode (location: (1,0)-(1,8))
            ├── lefts: (length: 0)
            ├── rest:
            │   @ SplatNode (location: (1,0)-(1,1))
            │   ├── operator_loc: (1,0)-(1,1) = "*"
            │   └── expression: ∅
            ├── rights: (length: 1)
            │   └── @ LocalVariableTargetNode (location: (1,3)-(1,4))
            │       ├── name: :a
            │       └── depth: 0
            ├── lparen_loc: ∅
            ├── rparen_loc: ∅
            ├── operator_loc: (1,5)-(1,6) = "="
            └── value:
                @ CallNode (location: (1,7)-(1,8))
                ├── flags: variable_call
                ├── receiver: ∅
                ├── call_operator_loc: ∅
                ├── name: :b
                ├── message_loc: (1,7)-(1,8) = "b"
                ├── opening_loc: ∅
                ├── arguments: ∅
                ├── closing_loc: ∅
                └── block: ∅
