@ ProgramNode (location: (1,0)-(4,5))
├── locals: []
└── statements:
    @ StatementsNode (location: (1,0)-(4,5))
    └── body: (length: 2)
        ├── @ LambdaNode (location: (1,0)-(3,1))
        │   ├── locals: [:_1, :_2]
        │   ├── locals_body_index: 2
        │   ├── operator_loc: (1,0)-(1,2) = "->"
        │   ├── opening_loc: (1,3)-(1,4) = "{"
        │   ├── closing_loc: (3,0)-(3,1) = "}"
        │   ├── parameters:
        │   │   @ NumberedParametersNode (location: (1,0)-(3,1))
        │   │   └── maximum: 2
        │   └── body:
        │       @ StatementsNode (location: (2,2)-(2,9))
        │       └── body: (length: 1)
        │           └── @ CallNode (location: (2,2)-(2,9))
        │               ├── flags: ∅
        │               ├── receiver:
        │               │   @ LocalVariableReadNode (location: (2,2)-(2,4))
        │               │   ├── name: :_1
        │               │   └── depth: 0
        │               ├── call_operator_loc: ∅
        │               ├── name: :+
        │               ├── message_loc: (2,5)-(2,6) = "+"
        │               ├── opening_loc: ∅
        │               ├── arguments:
        │               │   @ ArgumentsNode (location: (2,7)-(2,9))
        │               │   ├── flags: ∅
        │               │   └── arguments: (length: 1)
        │               │       └── @ LocalVariableReadNode (location: (2,7)-(2,9))
        │               │           ├── name: :_2
        │               │           └── depth: 0
        │               ├── closing_loc: ∅
        │               └── block: ∅
        └── @ ParenthesesNode (location: (4,0)-(4,5))
            ├── body:
            │   @ StatementsNode (location: (4,1)-(4,4))
            │   └── body: (length: 1)
            │       └── @ RangeNode (location: (4,1)-(4,4))
            │           ├── flags: ∅
            │           ├── left: ∅
            │           ├── right:
            │           │   @ IntegerNode (location: (4,3)-(4,4))
            │           │   └── flags: decimal
            │           └── operator_loc: (4,1)-(4,3) = ".."
            ├── opening_loc: (4,0)-(4,1) = "("
            └── closing_loc: (4,4)-(4,5) = ")"
