@ ProgramNode (location: (0...11))
├── locals: []
└── statements:
    @ StatementsNode (location: (0...11))
    └── body: (length: 1)
        └── @ PostExecutionNode (location: (0...11))
            ├── statements:
            │   @ StatementsNode (location: (6...9))
            │   └── body: (length: 1)
            │       └── @ CallNode (location: (6...9))
            │           ├── receiver: ∅
            │           ├── call_operator_loc: ∅
            │           ├── message_loc: (6...9) = "foo"
            │           ├── opening_loc: ∅
            │           ├── arguments: ∅
            │           ├── closing_loc: ∅
            │           ├── block: ∅
            │           ├── flags: variable_call
            │           └── name: "foo"
            ├── keyword_loc: (0...3) = "END"
            ├── opening_loc: (4...5) = "{"
            └── closing_loc: (10...11) = "}"
