@ ProgramNode (location: (1,0)-(8,12))
├── flags: ∅
├── locals: []
└── statements:
    @ StatementsNode (location: (1,0)-(8,12))
    ├── flags: ∅
    └── body: (length: 3)
        ├── @ CallNode (location: (1,0)-(3,2))
        │   ├── flags: newline, ignore_visibility
        │   ├── receiver: ∅
        │   ├── call_operator_loc: ∅
        │   ├── name: :f
        │   ├── message_loc: (1,0)-(1,1) = "f"
        │   ├── opening_loc: (1,1)-(1,2) = "("
        │   ├── arguments:
        │   │   @ ArgumentsNode (location: (1,2)-(3,1))
        │   │   ├── flags: contains_keywords
        │   │   └── arguments: (length: 1)
        │   │       └── @ KeywordHashNode (location: (1,2)-(3,1))
        │   │           ├── flags: symbol_keys
        │   │           └── elements: (length: 1)
        │   │               └── @ AssocNode (location: (1,2)-(3,1))
        │   │                   ├── flags: ∅
        │   │                   ├── key:
        │   │                   │   @ SymbolNode (location: (1,2)-(1,8))
        │   │                   │   ├── flags: static_literal, forced_us_ascii_encoding
        │   │                   │   ├── opening_loc: ∅
        │   │                   │   ├── value_loc: (1,2)-(1,7) = "state"
        │   │                   │   ├── closing_loc: (1,7)-(1,8) = ":"
        │   │                   │   └── unescaped: "state"
        │   │                   ├── value:
        │   │                   │   @ HashNode (location: (2,1)-(3,1))
        │   │                   │   ├── flags: static_literal
        │   │                   │   ├── opening_loc: (2,1)-(2,2) = "{"
        │   │                   │   ├── elements: (length: 0)
        │   │                   │   └── closing_loc: (3,0)-(3,1) = "}"
        │   │                   └── operator_loc: ∅
        │   ├── closing_loc: (3,1)-(3,2) = ")"
        │   └── block: ∅
        ├── @ CallNode (location: (5,0)-(6,2))
        │   ├── flags: newline, ignore_visibility
        │   ├── receiver: ∅
        │   ├── call_operator_loc: ∅
        │   ├── name: :f
        │   ├── message_loc: (5,0)-(5,1) = "f"
        │   ├── opening_loc: (5,1)-(5,2) = "("
        │   ├── arguments:
        │   │   @ ArgumentsNode (location: (5,2)-(6,1))
        │   │   ├── flags: contains_keywords
        │   │   └── arguments: (length: 1)
        │   │       └── @ KeywordHashNode (location: (5,2)-(6,1))
        │   │           ├── flags: symbol_keys
        │   │           └── elements: (length: 1)
        │   │               └── @ AssocNode (location: (5,2)-(6,1))
        │   │                   ├── flags: ∅
        │   │                   ├── key:
        │   │                   │   @ SymbolNode (location: (5,2)-(5,8))
        │   │                   │   ├── flags: static_literal, forced_us_ascii_encoding
        │   │                   │   ├── opening_loc: ∅
        │   │                   │   ├── value_loc: (5,2)-(5,7) = "state"
        │   │                   │   ├── closing_loc: (5,7)-(5,8) = ":"
        │   │                   │   └── unescaped: "state"
        │   │                   ├── value:
        │   │                   │   @ HashNode (location: (5,9)-(6,1))
        │   │                   │   ├── flags: static_literal
        │   │                   │   ├── opening_loc: (5,9)-(5,10) = "{"
        │   │                   │   ├── elements: (length: 0)
        │   │                   │   └── closing_loc: (6,0)-(6,1) = "}"
        │   │                   └── operator_loc: ∅
        │   ├── closing_loc: (6,1)-(6,2) = ")"
        │   └── block: ∅
        └── @ CallNode (location: (8,0)-(8,12))
            ├── flags: newline, ignore_visibility
            ├── receiver: ∅
            ├── call_operator_loc: ∅
            ├── name: :f
            ├── message_loc: (8,0)-(8,1) = "f"
            ├── opening_loc: (8,1)-(8,2) = "("
            ├── arguments:
            │   @ ArgumentsNode (location: (8,2)-(8,11))
            │   ├── flags: contains_keywords
            │   └── arguments: (length: 1)
            │       └── @ KeywordHashNode (location: (8,2)-(8,11))
            │           ├── flags: symbol_keys
            │           └── elements: (length: 1)
            │               └── @ AssocNode (location: (8,2)-(8,11))
            │                   ├── flags: ∅
            │                   ├── key:
            │                   │   @ SymbolNode (location: (8,2)-(8,8))
            │                   │   ├── flags: static_literal, forced_us_ascii_encoding
            │                   │   ├── opening_loc: ∅
            │                   │   ├── value_loc: (8,2)-(8,7) = "state"
            │                   │   ├── closing_loc: (8,7)-(8,8) = ":"
            │                   │   └── unescaped: "state"
            │                   ├── value:
            │                   │   @ HashNode (location: (8,9)-(8,11))
            │                   │   ├── flags: static_literal
            │                   │   ├── opening_loc: (8,9)-(8,10) = "{"
            │                   │   ├── elements: (length: 0)
            │                   │   └── closing_loc: (8,10)-(8,11) = "}"
            │                   └── operator_loc: ∅
            ├── closing_loc: (8,11)-(8,12) = ")"
            └── block: ∅
