@ ProgramNode (location: (1,0)-(3,11))
├── locals: [:foo, :bar]
└── statements:
    @ StatementsNode (location: (1,0)-(3,11))
    └── body: (length: 2)
        ├── @ LocalVariableWriteNode (location: (1,0)-(1,17))
        │   ├── name: :foo
        │   ├── depth: 0
        │   ├── name_loc: (1,0)-(1,3) = "foo"
        │   ├── value:
        │   │   @ LocalVariableWriteNode (location: (1,6)-(1,17))
        │   │   ├── name: :bar
        │   │   ├── depth: 0
        │   │   ├── name_loc: (1,6)-(1,9) = "bar"
        │   │   ├── value:
        │   │   │   @ CallNode (location: (1,12)-(1,17))
        │   │   │   ├── flags: ignore_visibility
        │   │   │   ├── receiver: ∅
        │   │   │   ├── call_operator_loc: ∅
        │   │   │   ├── name: :m
        │   │   │   ├── message_loc: (1,12)-(1,13) = "m"
        │   │   │   ├── opening_loc: ∅
        │   │   │   ├── arguments:
        │   │   │   │   @ ArgumentsNode (location: (1,14)-(1,17))
        │   │   │   │   ├── flags: ∅
        │   │   │   │   └── arguments: (length: 1)
        │   │   │   │       └── @ LocalVariableReadNode (location: (1,14)-(1,17))
        │   │   │   │           ├── name: :foo
        │   │   │   │           └── depth: 0
        │   │   │   ├── closing_loc: ∅
        │   │   │   └── block: ∅
        │   │   └── operator_loc: (1,10)-(1,11) = "="
        │   └── operator_loc: (1,4)-(1,5) = "="
        └── @ LocalVariableWriteNode (location: (3,0)-(3,11))
            ├── name: :foo
            ├── depth: 0
            ├── name_loc: (3,0)-(3,3) = "foo"
            ├── value:
            │   @ CallNode (location: (3,6)-(3,11))
            │   ├── flags: ignore_visibility
            │   ├── receiver: ∅
            │   ├── call_operator_loc: ∅
            │   ├── name: :m
            │   ├── message_loc: (3,6)-(3,7) = "m"
            │   ├── opening_loc: ∅
            │   ├── arguments:
            │   │   @ ArgumentsNode (location: (3,8)-(3,11))
            │   │   ├── flags: ∅
            │   │   └── arguments: (length: 1)
            │   │       └── @ LocalVariableReadNode (location: (3,8)-(3,11))
            │   │           ├── name: :foo
            │   │           └── depth: 0
            │   ├── closing_loc: ∅
            │   └── block: ∅
            └── operator_loc: (3,4)-(3,5) = "="