@ ProgramNode (location: (1,0)-(5,26))
├── locals: []
└── statements:
    @ StatementsNode (location: (1,0)-(5,26))
    └── body: (length: 3)
        ├── @ CallNode (location: (1,0)-(1,15))
        │   ├── flags: ignore_visibility
        │   ├── receiver: ∅
        │   ├── call_operator_loc: ∅
        │   ├── name: :assert
        │   ├── message_loc: (1,0)-(1,6) = "assert"
        │   ├── opening_loc: ∅
        │   ├── arguments:
        │   │   @ ArgumentsNode (location: (1,7)-(1,15))
        │   │   ├── flags: ∅
        │   │   └── arguments: (length: 1)
        │   │       └── @ KeywordHashNode (location: (1,7)-(1,15))
        │   │           ├── flags: symbol_keys
        │   │           └── elements: (length: 1)
        │   │               └── @ AssocNode (location: (1,7)-(1,15))
        │   │                   ├── key:
        │   │                   │   @ SymbolNode (location: (1,7)-(1,10))
        │   │                   │   ├── flags: forced_us_ascii_encoding
        │   │                   │   ├── opening_loc: ∅
        │   │                   │   ├── value_loc: (1,7)-(1,9) = "do"
        │   │                   │   ├── closing_loc: (1,9)-(1,10) = ":"
        │   │                   │   └── unescaped: "do"
        │   │                   ├── value:
        │   │                   │   @ TrueNode (location: (1,11)-(1,15))
        │   │                   └── operator_loc: ∅
        │   ├── closing_loc: ∅
        │   └── block: ∅
        ├── @ CallNode (location: (3,0)-(3,11))
        │   ├── flags: ignore_visibility
        │   ├── receiver: ∅
        │   ├── call_operator_loc: ∅
        │   ├── name: :assert
        │   ├── message_loc: (3,0)-(3,6) = "assert"
        │   ├── opening_loc: ∅
        │   ├── arguments:
        │   │   @ ArgumentsNode (location: (3,7)-(3,11))
        │   │   ├── flags: ∅
        │   │   └── arguments: (length: 1)
        │   │       └── @ CallNode (location: (3,7)-(3,11))
        │   │           ├── flags: variable_call, ignore_visibility
        │   │           ├── receiver: ∅
        │   │           ├── call_operator_loc: ∅
        │   │           ├── name: :dogs
        │   │           ├── message_loc: (3,7)-(3,11) = "dogs"
        │   │           ├── opening_loc: ∅
        │   │           ├── arguments: ∅
        │   │           ├── closing_loc: ∅
        │   │           └── block: ∅
        │   ├── closing_loc: ∅
        │   └── block: ∅
        └── @ CallNode (location: (5,0)-(5,26))
            ├── flags: ignore_visibility
            ├── receiver: ∅
            ├── call_operator_loc: ∅
            ├── name: :f
            ├── message_loc: (5,0)-(5,1) = "f"
            ├── opening_loc: ∅
            ├── arguments:
            │   @ ArgumentsNode (location: (5,2)-(5,26))
            │   ├── flags: ∅
            │   └── arguments: (length: 1)
            │       └── @ KeywordHashNode (location: (5,2)-(5,26))
            │           ├── flags: symbol_keys
            │           └── elements: (length: 1)
            │               └── @ AssocNode (location: (5,2)-(5,26))
            │                   ├── key:
            │                   │   @ SymbolNode (location: (5,2)-(5,4))
            │                   │   ├── flags: forced_us_ascii_encoding
            │                   │   ├── opening_loc: ∅
            │                   │   ├── value_loc: (5,2)-(5,3) = "x"
            │                   │   ├── closing_loc: (5,3)-(5,4) = ":"
            │                   │   └── unescaped: "x"
            │                   ├── value:
            │                   │   @ LambdaNode (location: (5,5)-(5,26))
            │                   │   ├── locals: []
            │                   │   ├── operator_loc: (5,5)-(5,7) = "->"
            │                   │   ├── opening_loc: (5,8)-(5,10) = "do"
            │                   │   ├── closing_loc: (5,23)-(5,26) = "end"
            │                   │   ├── parameters: ∅
            │                   │   └── body:
            │                   │       @ StatementsNode (location: (5,11)-(5,22))
            │                   │       └── body: (length: 1)
            │                   │           └── @ CallNode (location: (5,11)-(5,22))
            │                   │               ├── flags: ignore_visibility
            │                   │               ├── receiver: ∅
            │                   │               ├── call_operator_loc: ∅
            │                   │               ├── name: :meth
            │                   │               ├── message_loc: (5,11)-(5,15) = "meth"
            │                   │               ├── opening_loc: ∅
            │                   │               ├── arguments: ∅
            │                   │               ├── closing_loc: ∅
            │                   │               └── block:
            │                   │                   @ BlockNode (location: (5,16)-(5,22))
            │                   │                   ├── locals: []
            │                   │                   ├── parameters: ∅
            │                   │                   ├── body: ∅
            │                   │                   ├── opening_loc: (5,16)-(5,18) = "do"
            │                   │                   └── closing_loc: (5,19)-(5,22) = "end"
            │                   └── operator_loc: ∅
            ├── closing_loc: ∅
            └── block: ∅