@ ProgramNode (location: (0...33))
├── locals: []
└── statements:
    @ StatementsNode (location: (0...33))
    └── body: (length: 3)
        ├── @ PreExecutionNode (location: (0...15))
        │   ├── statements:
        │   │   @ StatementsNode (location: (10...13))
        │   │   └── body: (length: 1)
        │   │       └── @ CallNode (location: (10...13))
        │   │           ├── receiver: ∅
        │   │           ├── call_operator_loc: ∅
        │   │           ├── message_loc: (10...13) = "foo"
        │   │           ├── opening_loc: ∅
        │   │           ├── arguments: ∅
        │   │           ├── closing_loc: ∅
        │   │           ├── block: ∅
        │   │           ├── flags: variable_call
        │   │           └── name: "foo"
        │   ├── keyword_loc: (0...5) = "BEGIN"
        │   ├── opening_loc: (6...7) = "{"
        │   └── closing_loc: (14...15) = "}"
        ├── @ CallNode (location: (16...19))
        │   ├── receiver: ∅
        │   ├── call_operator_loc: ∅
        │   ├── message_loc: (16...19) = "bar"
        │   ├── opening_loc: ∅
        │   ├── arguments: ∅
        │   ├── closing_loc: ∅
        │   ├── block: ∅
        │   ├── flags: variable_call
        │   └── name: "bar"
        └── @ PostExecutionNode (location: (20...33))
            ├── statements:
            │   @ StatementsNode (location: (28...31))
            │   └── body: (length: 1)
            │       └── @ CallNode (location: (28...31))
            │           ├── receiver: ∅
            │           ├── call_operator_loc: ∅
            │           ├── message_loc: (28...31) = "baz"
            │           ├── opening_loc: ∅
            │           ├── arguments: ∅
            │           ├── closing_loc: ∅
            │           ├── block: ∅
            │           ├── flags: variable_call
            │           └── name: "baz"
            ├── keyword_loc: (20...23) = "END"
            ├── opening_loc: (24...25) = "{"
            └── closing_loc: (32...33) = "}"
