@ ProgramNode (location: (1,0)-(2,6))
├── locals: []
└── statements:
    @ StatementsNode (location: (1,0)-(2,6))
    └── body: (length: 2)
        ├── @ CallNode (location: (1,0)-(1,3))
        │   ├── receiver: ∅
        │   ├── call_operator_loc: ∅
        │   ├── message_loc: (1,0)-(1,3) = "foo"
        │   ├── opening_loc: ∅
        │   ├── arguments: ∅
        │   ├── closing_loc: ∅
        │   ├── block: ∅
        │   ├── flags: variable_call
        │   └── name: "foo"
        └── @ RangeNode (location: (2,0)-(2,6))
            ├── left: ∅
            ├── right:
            │   @ IntegerNode (location: (2,3)-(2,6))
            │   └── flags: decimal
            ├── operator_loc: (2,0)-(2,3) = "..."
            └── flags: exclude_end