@ ProgramNode (location: (1,0)-(7,10))
├── locals: []
└── statements:
    @ StatementsNode (location: (1,0)-(7,10))
    └── body: (length: 4)
        ├── @ YieldNode (location: (1,0)-(1,5))
        │   ├── keyword_loc: (1,0)-(1,5) = "yield"
        │   ├── lparen_loc: ∅
        │   ├── arguments: ∅
        │   └── rparen_loc: ∅
        ├── @ YieldNode (location: (3,0)-(3,9))
        │   ├── keyword_loc: (3,0)-(3,5) = "yield"
        │   ├── lparen_loc: ∅
        │   ├── arguments:
        │   │   @ ArgumentsNode (location: (3,6)-(3,9))
        │   │   ├── flags: ∅
        │   │   └── arguments: (length: 1)
        │   │       └── @ CallNode (location: (3,6)-(3,9))
        │   │           ├── flags: variable_call, ignore_visibility
        │   │           ├── receiver: ∅
        │   │           ├── call_operator_loc: ∅
        │   │           ├── name: :foo
        │   │           ├── message_loc: (3,6)-(3,9) = "foo"
        │   │           ├── opening_loc: ∅
        │   │           ├── arguments: ∅
        │   │           ├── closing_loc: ∅
        │   │           └── block: ∅
        │   └── rparen_loc: ∅
        ├── @ YieldNode (location: (5,0)-(5,7))
        │   ├── keyword_loc: (5,0)-(5,5) = "yield"
        │   ├── lparen_loc: (5,5)-(5,6) = "("
        │   ├── arguments: ∅
        │   └── rparen_loc: (5,6)-(5,7) = ")"
        └── @ YieldNode (location: (7,0)-(7,10))
            ├── keyword_loc: (7,0)-(7,5) = "yield"
            ├── lparen_loc: (7,5)-(7,6) = "("
            ├── arguments:
            │   @ ArgumentsNode (location: (7,6)-(7,9))
            │   ├── flags: ∅
            │   └── arguments: (length: 1)
            │       └── @ CallNode (location: (7,6)-(7,9))
            │           ├── flags: variable_call, ignore_visibility
            │           ├── receiver: ∅
            │           ├── call_operator_loc: ∅
            │           ├── name: :foo
            │           ├── message_loc: (7,6)-(7,9) = "foo"
            │           ├── opening_loc: ∅
            │           ├── arguments: ∅
            │           ├── closing_loc: ∅
            │           └── block: ∅
            └── rparen_loc: (7,9)-(7,10) = ")"