@ ProgramNode (location: (1,0)-(2,6))
├── locals: []
└── statements:
    @ StatementsNode (location: (1,0)-(2,6))
    └── body: (length: 2)
        ├── @ IfNode (location: (1,0)-(1,13))
        │   ├── if_keyword_loc: ∅
        │   ├── predicate:
        │   │   @ IntegerNode (location: (1,0)-(1,1))
        │   │   └── flags: decimal
        │   ├── then_keyword_loc: (1,2)-(1,3) = "?"
        │   ├── statements:
        │   │   @ StatementsNode (location: (1,4)-(1,9))
        │   │   └── body: (length: 1)
        │   │       └── @ CallNode (location: (1,4)-(1,9))
        │   │           ├── flags: ignore_visibility
        │   │           ├── receiver: ∅
        │   │           ├── call_operator_loc: ∅
        │   │           ├── name: :b
        │   │           ├── message_loc: (1,4)-(1,5) = "b"
        │   │           ├── opening_loc: (1,5)-(1,6) = "("
        │   │           ├── arguments:
        │   │           │   @ ArgumentsNode (location: (1,6)-(1,8))
        │   │           │   ├── flags: ∅
        │   │           │   └── arguments: (length: 1)
        │   │           │       └── @ StringNode (location: (1,6)-(1,8))
        │   │           │           ├── flags: ∅
        │   │           │           ├── opening_loc: (1,6)-(1,7) = "'"
        │   │           │           ├── content_loc: (1,7)-(1,7) = ""
        │   │           │           ├── closing_loc: (1,7)-(1,8) = "'"
        │   │           │           └── unescaped: ""
        │   │           ├── closing_loc: (1,8)-(1,9) = ")"
        │   │           └── block: ∅
        │   ├── consequent:
        │   │   @ ElseNode (location: (1,10)-(1,13))
        │   │   ├── else_keyword_loc: (1,10)-(1,11) = ":"
        │   │   ├── statements:
        │   │   │   @ StatementsNode (location: (1,12)-(1,13))
        │   │   │   └── body: (length: 1)
        │   │   │       └── @ IntegerNode (location: (1,12)-(1,13))
        │   │   │           └── flags: decimal
        │   │   └── end_keyword_loc: ∅
        │   └── end_keyword_loc: ∅
        └── @ CallNode (location: (2,0)-(2,6))
            ├── flags: ignore_visibility
            ├── receiver: ∅
            ├── call_operator_loc: ∅
            ├── name: :a
            ├── message_loc: (2,0)-(2,1) = "a"
            ├── opening_loc: ∅
            ├── arguments:
            │   @ ArgumentsNode (location: (2,2)-(2,6))
            │   ├── flags: ∅
            │   └── arguments: (length: 1)
            │       └── @ KeywordHashNode (location: (2,2)-(2,6))
            │           ├── flags: symbol_keys
            │           └── elements: (length: 1)
            │               └── @ AssocNode (location: (2,2)-(2,6))
            │                   ├── key:
            │                   │   @ SymbolNode (location: (2,2)-(2,4))
            │                   │   ├── flags: forced_us_ascii_encoding
            │                   │   ├── opening_loc: ∅
            │                   │   ├── value_loc: (2,2)-(2,3) = "d"
            │                   │   ├── closing_loc: (2,3)-(2,4) = ":"
            │                   │   └── unescaped: "d"
            │                   ├── value:
            │                   │   @ IntegerNode (location: (2,5)-(2,6))
            │                   │   └── flags: decimal
            │                   └── operator_loc: ∅
            ├── closing_loc: ∅
            └── block: ∅
