@ ProgramNode (location: (1,0)-(1,6))
├── locals: []
└── statements:
    @ StatementsNode (location: (1,0)-(1,6))
    └── body: (length: 1)
        └── @ HashNode (location: (1,0)-(1,6))
            ├── opening_loc: (1,0)-(1,1) = "{"
            ├── elements: (length: 1)
            │   └── @ AssocNode (location: (1,2)-(1,4))
            │       ├── key:
            │       │   @ SymbolNode (location: (1,2)-(1,4))
            │       │   ├── flags: forced_us_ascii_encoding
            │       │   ├── opening_loc: ∅
            │       │   ├── value_loc: (1,2)-(1,3) = "y"
            │       │   ├── closing_loc: (1,3)-(1,4) = ":"
            │       │   └── unescaped: "y"
            │       ├── value:
            │       │   @ ImplicitNode (location: (1,2)-(1,4))
            │       │   └── value:
            │       │       @ CallNode (location: (1,2)-(1,4))
            │       │       ├── flags: ignore_visibility
            │       │       ├── receiver: ∅
            │       │       ├── call_operator_loc: ∅
            │       │       ├── name: :y
            │       │       ├── message_loc: (1,2)-(1,3) = "y"
            │       │       ├── opening_loc: ∅
            │       │       ├── arguments: ∅
            │       │       ├── closing_loc: ∅
            │       │       └── block: ∅
            │       └── operator_loc: ∅
            └── closing_loc: (1,5)-(1,6) = "}"