@ DocumentNode (location: (1:0)-(1:21))
└── children: (1 item)
    └── @ HTMLElementNode (location: (1:0)-(1:21))
        ├── open_tag:
        │   └── @ HTMLOpenTagNode (location: (1:0)-(1:4))
        │       ├── tag_opening: "<" (location: (1:0)-(1:1))
        │       ├── tag_name: "h1" (location: (1:1)-(1:3))
        │       ├── tag_closing: ">" (location: (1:3)-(1:4))
        │       ├── children: []
        │       └── is_void: false
        │
        ├── tag_name: "h1" (location: (1:1)-(1:3))
        ├── body: (1 item)
        │   └── @ ERBContentNode (location: (1:4)-(1:16))
        │       ├── tag_opening: "<%=" (location: (1:4)-(1:7))
        │       ├── content: " hello " (location: (1:7)-(1:14))
        │       ├── tag_closing: "%>" (location: (1:14)-(1:16))
        │       ├── parsed: true
        │       └── valid: true
        │
        ├── close_tag:
        │   └── @ HTMLCloseTagNode (location: (1:16)-(1:21))
        │       ├── tag_opening: "</" (location: (1:16)-(1:18))
        │       ├── tag_name: "h1" (location: (1:18)-(1:20))
        │       └── tag_closing: ">" (location: (1:20)-(1:21))
        │
        └── is_void: false