@ ProgramNode (location: (1,0)-(1,24))
├── flags: ∅
├── locals: []
└── statements:
    @ StatementsNode (location: (1,0)-(1,24))
    ├── flags: ∅
    └── body: (length: 1)
        └── @ HashNode (location: (1,0)-(1,24))
            ├── flags: newline
            ├── opening_loc: (1,0)-(1,1) = "{"
            ├── elements: (length: 1)
            │   └── @ AssocNode (location: (1,1)-(1,23))
            │       ├── flags: ∅
            │       ├── key:
            │       │   @ SymbolNode (location: (1,1)-(1,3))
            │       │   ├── flags: static_literal, forced_us_ascii_encoding
            │       │   ├── opening_loc: ∅
            │       │   ├── value_loc: (1,1)-(1,2) = "a"
            │       │   ├── closing_loc: (1,2)-(1,3) = ":"
            │       │   └── unescaped: "a"
            │       ├── value:
            │       │   @ IfNode (location: (1,4)-(1,23))
            │       │   ├── flags: newline
            │       │   ├── if_keyword_loc: (1,4)-(1,6) = "if"
            │       │   ├── predicate:
            │       │   │   @ TrueNode (location: (1,7)-(1,11))
            │       │   │   └── flags: static_literal
            │       │   ├── then_keyword_loc: (1,12)-(1,16) = "then"
            │       │   ├── statements:
            │       │   │   @ StatementsNode (location: (1,17)-(1,19))
            │       │   │   ├── flags: ∅
            │       │   │   └── body: (length: 1)
            │       │   │       └── @ IntegerNode (location: (1,17)-(1,19))
            │       │   │           ├── flags: newline, static_literal, decimal
            │       │   │           └── value: 42
            │       │   ├── subsequent: ∅
            │       │   └── end_keyword_loc: (1,20)-(1,23) = "end"
            │       └── operator_loc: ∅
            └── closing_loc: (1,23)-(1,24) = "}"
