@ ProgramNode (location: (1,0)-(3,14))
├── locals: []
└── statements:
    @ StatementsNode (location: (1,0)-(3,14))
    └── body: (length: 2)
        ├── @ CallNode (location: (1,0)-(1,11))
        │   ├── flags: ignore_visibility
        │   ├── receiver: ∅
        │   ├── call_operator_loc: ∅
        │   ├── name: :m
        │   ├── message_loc: (1,0)-(1,1) = "m"
        │   ├── opening_loc: ∅
        │   ├── arguments:
        │   │   @ ArgumentsNode (location: (1,2)-(1,4))
        │   │   ├── flags: ∅
        │   │   └── arguments: (length: 1)
        │   │       └── @ ArrayNode (location: (1,2)-(1,4))
        │   │           ├── flags: ∅
        │   │           ├── elements: (length: 0)
        │   │           ├── opening_loc: (1,2)-(1,3) = "["
        │   │           └── closing_loc: (1,3)-(1,4) = "]"
        │   ├── closing_loc: ∅
        │   └── block:
        │       @ BlockNode (location: (1,5)-(1,11))
        │       ├── locals: []
        │       ├── parameters: ∅
        │       ├── body: ∅
        │       ├── opening_loc: (1,5)-(1,7) = "do"
        │       └── closing_loc: (1,8)-(1,11) = "end"
        └── @ CallNode (location: (3,0)-(3,14))
            ├── flags: ignore_visibility
            ├── receiver: ∅
            ├── call_operator_loc: ∅
            ├── name: :m
            ├── message_loc: (3,0)-(3,1) = "m"
            ├── opening_loc: ∅
            ├── arguments:
            │   @ ArgumentsNode (location: (3,2)-(3,7))
            │   ├── flags: ∅
            │   └── arguments: (length: 2)
            │       ├── @ ArrayNode (location: (3,2)-(3,4))
            │       │   ├── flags: ∅
            │       │   ├── elements: (length: 0)
            │       │   ├── opening_loc: (3,2)-(3,3) = "["
            │       │   └── closing_loc: (3,3)-(3,4) = "]"
            │       └── @ IntegerNode (location: (3,6)-(3,7))
            │           ├── flags: decimal
            │           └── value: 1
            ├── closing_loc: ∅
            └── block:
                @ BlockNode (location: (3,8)-(3,14))
                ├── locals: []
                ├── parameters: ∅
                ├── body: ∅
                ├── opening_loc: (3,8)-(3,10) = "do"
                └── closing_loc: (3,11)-(3,14) = "end"