@ ProgramNode (location: (1,0)-(1,16))
├── locals: []
└── statements:
    @ StatementsNode (location: (1,0)-(1,16))
    └── body: (length: 1)
        └── @ CallNode (location: (1,0)-(1,16))
            ├── flags: 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)-(1,15))
            │   ├── flags: contains_keyword_splat
            │   └── arguments: (length: 2)
            │       ├── @ IntegerNode (location: (1,2)-(1,3))
            │       │   ├── flags: decimal
            │       │   └── value: 1
            │       └── @ KeywordHashNode (location: (1,5)-(1,15))
            │           ├── flags: ∅
            │           └── elements: (length: 2)
            │               ├── @ AssocNode (location: (1,5)-(1,10))
            │               │   ├── key:
            │               │   │   @ SymbolNode (location: (1,5)-(1,8))
            │               │   │   ├── flags: forced_us_ascii_encoding
            │               │   │   ├── opening_loc: ∅
            │               │   │   ├── value_loc: (1,5)-(1,7) = "kw"
            │               │   │   ├── closing_loc: (1,7)-(1,8) = ":"
            │               │   │   └── unescaped: "kw"
            │               │   ├── value:
            │               │   │   @ IntegerNode (location: (1,9)-(1,10))
            │               │   │   ├── flags: decimal
            │               │   │   └── value: 2
            │               │   └── operator_loc: ∅
            │               └── @ AssocSplatNode (location: (1,12)-(1,15))
            │                   ├── value:
            │                   │   @ IntegerNode (location: (1,14)-(1,15))
            │                   │   ├── flags: decimal
            │                   │   └── value: 3
            │                   └── operator_loc: (1,12)-(1,14) = "**"
            ├── closing_loc: (1,15)-(1,16) = ")"
            └── block: ∅