@ DocumentNode (location: (1:0)-(6:0))
└── children: (2 items)
    ├── @ HTMLElementNode (location: (1:0)-(5:6))
    │   ├── open_tag:
    │   │   └── @ HTMLOpenTagNode (location: (1:0)-(5:1))
    │   │       ├── tag_opening: "<" (location: (1:0)-(1:1))
    │   │       ├── tag_name: "h1" (location: (1:1)-(1:3))
    │   │       ├── tag_closing: ">" (location: (5:0)-(5:1))
    │   │       ├── children: (1 item)
    │   │       │   └── @ ERBIfNode (location: (2:2)-(4:11))
    │   │       │       ├── tag_opening: "<%" (location: (2:2)-(2:4))
    │   │       │       ├── content: " if id? " (location: (2:4)-(2:12))
    │   │       │       ├── tag_closing: "%>" (location: (2:12)-(2:14))
    │   │       │       ├── statements: (1 item)
    │   │       │       │   └── @ HTMLAttributeNode (location: (3:4)-(3:14))
    │   │       │       │       ├── name:
    │   │       │       │       │   └── @ HTMLAttributeNameNode (location: (3:4)-(3:6))
    │   │       │       │       │       └── name: "id" (location: (3:4)-(3:6))
    │   │       │       │       │
    │   │       │       │       ├── equals: "=" (location: (3:6)-(3:7))
    │   │       │       │       └── value:
    │   │       │       │           └── @ HTMLAttributeValueNode (location: (3:7)-(3:14))
    │   │       │       │               ├── open_quote: """ (location: (3:7)-(3:8))
    │   │       │       │               ├── children: (1 item)
    │   │       │       │               │   └── @ LiteralNode (location: (3:8)-(3:13))
    │   │       │       │               │       └── content: "title"
    │   │       │       │               │
    │   │       │       │               ├── close_quote: """ (location: (3:13)-(3:14))
    │   │       │       │               └── quoted: true
    │   │       │       │
    │   │       │       │
    │   │       │       ├── subsequent: ∅
    │   │       │       └── end_node:
    │   │       │           └── @ ERBEndNode (location: (4:2)-(4:11))
    │   │       │               ├── tag_opening: "<%" (location: (4:2)-(4:4))
    │   │       │               ├── content: " end " (location: (4:4)-(4:9))
    │   │       │               └── tag_closing: "%>" (location: (4:9)-(4:11))
    │   │       │
    │   │       │
    │   │       └── is_void: false
    │   │
    │   ├── tag_name: "h1" (location: (1:1)-(1:3))
    │   ├── body: []
    │   ├── close_tag:
    │   │   └── @ HTMLCloseTagNode (location: (5:1)-(5:6))
    │   │       ├── tag_opening: "</" (location: (5:1)-(5:3))
    │   │       ├── tag_name: "h1" (location: (5:3)-(5:5))
    │   │       └── tag_closing: ">" (location: (5:5)-(5:6))
    │   │
    │   └── is_void: false
    │
    └── @ HTMLTextNode (location: (5:6)-(6:0))
        └── content: "\n"