@ ProgramNode (location: (1,0)-(1,9))
├── locals: [:s]
└── statements:
    @ StatementsNode (location: (1,0)-(1,9))
    └── body: (length: 1)
        └── @ LocalVariableWriteNode (location: (1,0)-(1,9))
            ├── name: :s
            ├── depth: 0
            ├── name_loc: (1,0)-(1,1) = "s"
            ├── value:
            │   @ StringNode (location: (1,4)-(1,9))
            │   ├── flags: forced_utf8_encoding
            │   ├── opening_loc: (1,4)-(1,9) = "<<eos"
            │   ├── content_loc: (2,0)-(3,0) = "a\\xE9b\n"
            │   ├── closing_loc: (3,0)-(4,0) = "eos\n"
            │   └── unescaped: "a\xE9b\n"
            └── operator_loc: (1,2)-(1,3) = "="