@ ProgramNode (location: (1,0)-(3,1))
├── locals: []
└── statements:
    @ StatementsNode (location: (1,0)-(3,1))
    └── body: (length: 1)
        └── @ PostExecutionNode (location: (1,0)-(3,1))
            ├── statements:
            │   @ StatementsNode (location: (2,0)-(2,3))
            │   └── body: (length: 1)
            │       └── @ CallNode (location: (2,0)-(2,3))
            │           ├── flags: variable_call
            │           ├── receiver: ∅
            │           ├── call_operator_loc: ∅
            │           ├── name: :foo
            │           ├── message_loc: (2,0)-(2,3) = "foo"
            │           ├── opening_loc: ∅
            │           ├── arguments: ∅
            │           ├── closing_loc: ∅
            │           └── block: ∅
            ├── keyword_loc: (1,0)-(1,3) = "END"
            ├── opening_loc: (1,4)-(1,5) = "{"
            └── closing_loc: (3,0)-(3,1) = "}"
