@ ProgramNode (location: (0...27))
├── locals: []
└── statements:
    @ StatementsNode (location: (0...27))
    └── body: (length: 2)
        ├── @ CallNode (location: (0...11))
        │   ├── receiver: ∅
        │   ├── call_operator_loc: ∅
        │   ├── message_loc: (0...1) = "m"
        │   ├── opening_loc: ∅
        │   ├── arguments:
        │   │   @ ArgumentsNode (location: (2...4))
        │   │   └── arguments: (length: 1)
        │   │       └── @ ArrayNode (location: (2...4))
        │   │           ├── elements: (length: 0)
        │   │           ├── opening_loc: (2...3) = "["
        │   │           └── closing_loc: (3...4) = "]"
        │   ├── closing_loc: ∅
        │   ├── block:
        │   │   @ BlockNode (location: (5...11))
        │   │   ├── locals: []
        │   │   ├── parameters: ∅
        │   │   ├── body: ∅
        │   │   ├── opening_loc: (5...7) = "do"
        │   │   └── closing_loc: (8...11) = "end"
        │   ├── flags: ∅
        │   └── name: "m"
        └── @ CallNode (location: (13...27))
            ├── receiver: ∅
            ├── call_operator_loc: ∅
            ├── message_loc: (13...14) = "m"
            ├── opening_loc: ∅
            ├── arguments:
            │   @ ArgumentsNode (location: (15...20))
            │   └── arguments: (length: 2)
            │       ├── @ ArrayNode (location: (15...17))
            │       │   ├── elements: (length: 0)
            │       │   ├── opening_loc: (15...16) = "["
            │       │   └── closing_loc: (16...17) = "]"
            │       └── @ IntegerNode (location: (19...20))
            │           └── flags: decimal
            ├── closing_loc: ∅
            ├── block:
            │   @ BlockNode (location: (21...27))
            │   ├── locals: []
            │   ├── parameters: ∅
            │   ├── body: ∅
            │   ├── opening_loc: (21...23) = "do"
            │   └── closing_loc: (24...27) = "end"
            ├── flags: ∅
            └── name: "m"
