--- title: Definitions --- # Definitions The definitions below are an essential part of the parser. ## Node Types The type of a node is determined during parsing and represented by one of the elements in the list below. | Type | Description | ---- | ----------- | `HDOM_TYPE_ELEMENT` | Start tag (i.e. ``) | `HDOM_TYPE_COMMENT` | HTML comment (i.e. ``) | `HDOM_TYPE_TEXT` | Plain text (i.e. `Hello, World!`) | `HDOM_TYPE_ENDTAG` | End tag (i.e. ``) | `HDOM_TYPE_ROOT` | Root element. There can always only be one root element in the DOM. | `HDOM_TYPE_UNKNOWN` | Unknown type (i.e. CDATA, DOCTYPE, etc...) ### Example ```html Hello, World! ``` _Note_: `HDOM_TYPE_ROOT` always exists regardless of the actual document structure. | HTML | Node Type | ---- | --------- | | `HDOM_TYPE_ROOT` | `` | `HDOM_TYPE_UNKNOWN` | `` | `HDOM_TYPE_ELEMENT` | `` | `HDOM_TYPE_COMMENT` | `` | `HDOM_TYPE_ENDTAG` | `Hello, World!` | `HDOM_TYPE_TEXT` ## Quote Types Identifies the quoting type on attribute values. | Type | Description | ---- | ----------- | `HDOM_QUOTE_DOUBLE` | Double quotes (`""`) | `HDOM_QUOTE_SINGLE` | Single quotes (`''`) | `HDOM_QUOTE_NO` | Not quoted (flag) _Note_: Attributes with no values (flags) are stored as `HDOM_QUOTE_NO`. ### Example ```html ``` | Attribute | Description | --------- | ----------- | `class="paragraph"` | `HDOM_QUOTE_DOUBLE` | `id='info1'` | `HDOM_QUOTE_SINGLE` | `hidden` | `HDOM_QUOTE_NO` ## Node Info Types Each node stores additional information (metadata) that is identified by the elements below. | Type | Description | ---- | ----------- | `HDOM_INFO_BEGIN` | Cursor position for the start tag of a node. | `HDOM_INFO_END` | Cursor position for the end tag of a node. A value of zero indicates a node with no end tag (missing closing tag). | `HDOM_INFO_QUOTE` | Quote type for attribute values. The value must be an element of [Quote Type](#quote-types). | `HDOM_INFO_SPACE` | Array of whitespace around attributes (see [Attribute Whitespace](#attribute-whitespace)). | `HDOM_INFO_TEXT` | Non-HTML text in tags (i.e. comments, doctype, etc...). | `HDOM_INFO_INNER` | Inner text of a node. | `HDOM_INFO_OUTER` | Outer text of a node. | `HDOM_INFO_ENDSPACE` | Whitespace at the end of a tag before the closing bracket. ## Attribute Whitespace Whitespace around attributes is stored in the form of an array with three elements: | Element | Description | ------- | ----------- | `0` | Whitespace before the attribute name. | `1` | Whitespace between attribute name and the equal sign. | `2` | Whitespace between the equal sign and the attribute value ### Example ```html ``` _Note_: Whitespace before attribute names is not displayed in the browser. It is, however, part of the attributes. | Attribute | Description | --------- | ----------- | ` class="paragraph"` | `[0] => ' ', [1] => '', [2] => ''` | ` id = 'info1'` | `[0] => ' ', [1] => ' ', [2] => ' '` | `hidden` | `[0] => '', [1] => '', [2] => ''`