@ ProgramNode (location: (1,0)-(3,19))
├── locals: []
└── statements:
    @ StatementsNode (location: (1,0)-(3,19))
    └── body: (length: 2)
        ├── @ CallNode (location: (1,0)-(1,14))
        │   ├── flags: ∅
        │   ├── receiver: ∅
        │   ├── call_operator_loc: ∅
        │   ├── name: :fun
        │   ├── message_loc: (1,0)-(1,3) = "fun"
        │   ├── opening_loc: (1,3)-(1,4) = "("
        │   ├── arguments:
        │   │   @ ArgumentsNode (location: (1,4)-(1,13))
        │   │   ├── flags: ∅
        │   │   └── arguments: (length: 2)
        │   │       ├── @ CallNode (location: (1,4)-(1,7))
        │   │       │   ├── flags: variable_call
        │   │       │   ├── receiver: ∅
        │   │       │   ├── call_operator_loc: ∅
        │   │       │   ├── name: :foo
        │   │       │   ├── message_loc: (1,4)-(1,7) = "foo"
        │   │       │   ├── opening_loc: ∅
        │   │       │   ├── arguments: ∅
        │   │       │   ├── closing_loc: ∅
        │   │       │   └── block: ∅
        │   │       └── @ SplatNode (location: (1,9)-(1,13))
        │   │           ├── operator_loc: (1,9)-(1,10) = "*"
        │   │           └── expression:
        │   │               @ CallNode (location: (1,10)-(1,13))
        │   │               ├── flags: variable_call
        │   │               ├── receiver: ∅
        │   │               ├── call_operator_loc: ∅
        │   │               ├── name: :bar
        │   │               ├── message_loc: (1,10)-(1,13) = "bar"
        │   │               ├── opening_loc: ∅
        │   │               ├── arguments: ∅
        │   │               ├── closing_loc: ∅
        │   │               └── block: ∅
        │   ├── closing_loc: (1,13)-(1,14) = ")"
        │   └── block: ∅
        └── @ CallNode (location: (3,0)-(3,19))
            ├── flags: ∅
            ├── receiver: ∅
            ├── call_operator_loc: ∅
            ├── name: :fun
            ├── message_loc: (3,0)-(3,3) = "fun"
            ├── opening_loc: (3,3)-(3,4) = "("
            ├── arguments:
            │   @ ArgumentsNode (location: (3,4)-(3,13))
            │   ├── flags: ∅
            │   └── arguments: (length: 2)
            │       ├── @ CallNode (location: (3,4)-(3,7))
            │       │   ├── flags: variable_call
            │       │   ├── receiver: ∅
            │       │   ├── call_operator_loc: ∅
            │       │   ├── name: :foo
            │       │   ├── message_loc: (3,4)-(3,7) = "foo"
            │       │   ├── opening_loc: ∅
            │       │   ├── arguments: ∅
            │       │   ├── closing_loc: ∅
            │       │   └── block: ∅
            │       └── @ SplatNode (location: (3,9)-(3,13))
            │           ├── operator_loc: (3,9)-(3,10) = "*"
            │           └── expression:
            │               @ CallNode (location: (3,10)-(3,13))
            │               ├── flags: variable_call
            │               ├── receiver: ∅
            │               ├── call_operator_loc: ∅
            │               ├── name: :bar
            │               ├── message_loc: (3,10)-(3,13) = "bar"
            │               ├── opening_loc: ∅
            │               ├── arguments: ∅
            │               ├── closing_loc: ∅
            │               └── block: ∅
            ├── closing_loc: (3,19)-(3,20) = ")"
            └── block:
                @ BlockArgumentNode (location: (3,15)-(3,19))
                ├── expression:
                │   @ CallNode (location: (3,16)-(3,19))
                │   ├── flags: variable_call
                │   ├── receiver: ∅
                │   ├── call_operator_loc: ∅
                │   ├── name: :baz
                │   ├── message_loc: (3,16)-(3,19) = "baz"
                │   ├── opening_loc: ∅
                │   ├── arguments: ∅
                │   ├── closing_loc: ∅
                │   └── block: ∅
                └── operator_loc: (3,15)-(3,16) = "&"
