@ ProgramNode (location: (0...10))
├── locals: []
└── statements:
    @ StatementsNode (location: (0...10))
    └── body: (length: 1)
        └── @ HashNode (location: (0...10))
            ├── opening_loc: (0...1) = "{"
            ├── elements: (length: 1)
            │   └── @ AssocNode (location: (2...8))
            │       ├── key:
            │       │   @ SymbolNode (location: (2...6))
            │       │   ├── opening_loc: ∅
            │       │   ├── value_loc: (2...5) = "foo"
            │       │   ├── closing_loc: (5...6) = ":"
            │       │   └── unescaped: "foo"
            │       ├── value:
            │       │   @ IntegerNode (location: (7...8))
            │       │   └── flags: decimal
            │       └── operator_loc: ∅
            └── closing_loc: (9...10) = "}"
