@ ProgramNode (location: (1,0)-(1,7))
├── locals: []
└── statements:
    @ StatementsNode (location: (1,0)-(1,7))
    └── body: (length: 1)
        └── @ YieldNode (location: (1,0)-(1,7))
            ├── keyword_loc: (1,0)-(1,5) = "yield"
            ├── lparen_loc: (1,5)-(1,6) = "("
            ├── arguments: ∅
            └── rparen_loc: (1,6)-(1,7) = ")"