@ ProgramNode (location: (0...10))
├── locals: [:s]
└── statements:
    @ StatementsNode (location: (0...10))
    └── body: (length: 1)
        └── @ LocalVariableWriteNode (location: (0...10))
            ├── name: :s
            ├── depth: 0
            ├── name_loc: (0...1) = "s"
            ├── value:
            │   @ StringNode (location: (4...10))
            │   ├── opening_loc: (4...10) = "<<-EOS"
            │   ├── content_loc: (11...23) = "a\\247b\ncöd\n"
            │   ├── closing_loc: (23...27) = "EOS\n"
            │   └── unescaped: "a\xA7b\ncöd\n"
            └── operator_loc: (2...3) = "="
