@ ProgramNode (location: (1,0)-(1,7))
├── locals: []
└── statements:
    @ StatementsNode (location: (1,0)-(1,7))
    └── body: (length: 1)
        └── @ CallNode (location: (1,0)-(1,7))
            ├── receiver:
            │   @ IntegerNode (location: (1,0)-(1,1))
            │   └── flags: decimal
            ├── call_operator_loc: ∅
            ├── message_loc: (1,2)-(1,5) = "<=>"
            ├── opening_loc: ∅
            ├── arguments:
            │   @ ArgumentsNode (location: (1,6)-(1,7))
            │   └── arguments: (length: 1)
            │       └── @ IntegerNode (location: (1,6)-(1,7))
            │           └── flags: decimal
            ├── closing_loc: ∅
            ├── block: ∅
            ├── flags: ∅
            └── name: "<=>"