Enum NodeKind 

pub enum NodeKind {
    Heading {
        level: u8,
        text: String,
        id: Option<String>,
    },
    Paragraph,
    CodeBlock {
        language: Option<String>,
        code: String,
    },
    ThematicBreak,
    List {
        ordered: bool,
        start: Option<u32>,
        tight: bool,
    },
    ListItem,
    DefinitionList,
    DefinitionTerm,
    DefinitionDescription,
    TaskCheckbox {
        checked: bool,
    },
    Blockquote,
    Admonition {
        kind: AdmonitionKind,
        title: Option<String>,
        icon: Option<String>,
        style: AdmonitionStyle,
    },
    TabGroup,
    TabItem {
        title: String,
    },
    SliderDeck {
        timer_seconds: Option<u32>,
    },
    Slide {
        vertical: bool,
    },
    Table {
        alignments: Vec<TableAlignment>,
    },
    TableRow {
        header: bool,
    },
    TableCell {
        header: bool,
        alignment: TableAlignment,
    },
    HtmlBlock {
        html: String,
    },
    FootnoteDefinition {
        label: String,
    },
    Text(String),
    TaskCheckboxInline {
        checked: bool,
    },
    Emphasis,
    Strong,
    StrongEmphasis,
    Strikethrough,
    Mark,
    Superscript,
    Subscript,
    Link {
        url: String,
        title: Option<String>,
    },
    LinkReference {
        label: String,
        suffix: String,
    },
    FootnoteReference {
        label: String,
    },
    Image {
        url: String,
        alt: String,
    },
    CodeSpan(String),
    InlineHtml(String),
    HardBreak,
    SoftBreak,
    PlatformMention {
        username: String,
        platform: String,
        display: Option<String>,
    },
    InlineMath {
        content: String,
    },
    DisplayMath {
        content: String,
    },
    MermaidDiagram {
        content: String,
    },
}

All supported block and inline AST node kinds.

Variants

Heading

ATX or setext heading node.

Fields

level: u8

Heading level, typically in range 1..=6.

text: String

Plain heading text content.

id: Option<String>

Explicit heading id, e.g. ### Title {#custom-id}.

When present, the renderer should emit it as id="..." on the heading element.

Paragraph

Paragraph container.

CodeBlock

Fenced or indented code block.

Fields

language: Option<String>

Optional language/info string.

code: String

Raw code block contents.

ThematicBreak

Horizontal rule (---, ***, ___).

List

Ordered or unordered list container.

Fields

ordered: bool

Whether this is an ordered list.

start: Option<u32>

Starting number for ordered lists.

tight: bool

Whether list items are tight (no blank separators).

ListItem

List item container.

DefinitionList

Extended definition lists (Markdown Guide / Markdown Extra-style).

Rendering convention:

• A DefinitionList contains alternating DefinitionTerm (<dt>) and DefinitionDescription (<dd>) children.
• DefinitionTerm should contain inline children.
• DefinitionDescription should contain block children.

DefinitionTerm

Definition term (dt) item.

DefinitionDescription

Definition description (dd) item.

TaskCheckbox

GFM task list checkbox marker for a list item.

This is emitted by the list parser when a list item begins with [ ] or [x] / [X].

Rendering convention:

• This node is expected to appear as the first child inside a ListItem.
• The HTML renderer will convert it into a themed checkbox icon.

Fields

checked: bool

Whether checkbox is checked.

Blockquote

Blockquote container.

Admonition

GitHub-style admonition / alert (GFM extension).

This is created by a post-parse transformation that recognizes a special first line inside a blockquote (e.g. [!NOTE]) and removes that marker.

Fields

kind: AdmonitionKind

Admonition semantic kind.

title: Option<String>

Optional custom title for the admonition header.

Used by extended GFM-style admonitions (e.g. > [😂 Happy Header]).

icon: Option<String>

Optional custom icon content (typically a Unicode emoji) for the title.

Rendered as text (not SVG) and must be styled by CSS.

style: AdmonitionStyle

Render variant.

TabGroup

Extended tab blocks.

Syntax (container + items):

:::tab
@tab Title
Content...
:::

Children convention:

• A TabGroup contains one or more TabItem children.
• Each TabItem contains block children representing the tab panel content.

TabItem

A single tab item inside a tab group.

Fields

title: String

User-visible tab title.

SliderDeck

Extended slide decks (Reveal.js-like syntax, rendered as a simple slideshow).

Syntax:

@slidestart
slide 1
---
slide 2
@slideend

Optional timer (seconds per slide): @slidestart:t5.

Children convention:

• A SliderDeck contains one or more Slide children.
• Each Slide contains block children representing the slide content.

Fields

timer_seconds: Option<u32>

Optional per-slide timer value in seconds.

Slide

A single slide inside a slider deck.

Fields

vertical: bool

True if this slide started after a vertical separator (--).

The current viewer treats slides as a single linear sequence (left/right). This flag is preserved for future vertical navigation.

Table

GFM table (pipe table extension).

Children convention:

• Each child is a TableRow.
• Each TableRow contains TableCell children.

Fields

alignments: Vec<TableAlignment>

Per-column alignments.

TableRow

A single table row.

Fields

header: bool

Whether this row is part of the table header.

TableCell

A single table cell.

Fields

header: bool

Whether this cell is in a header row.

alignment: TableAlignment

Effective alignment for this cell.

HtmlBlock

Raw block-level HTML fragment.

Fields

html: String

Raw HTML source.

FootnoteDefinition

GFM-style footnote definition (extension).

Syntax:

• [^label]: definition text
• Continuation lines may be indented.

Rendering convention:

• This node should not be rendered in place.
• Instead, the renderer collects referenced footnotes and emits a footnotes section at the end of the document.

Fields

label: String

Footnote label (without [^/]).

Text(String)

Plain text inline content.

TaskCheckboxInline

Inline task checkbox marker (extension).

This is emitted when a paragraph begins with a task marker like [ ] / [x] / [X] .

Rendering convention:

• The HTML renderer converts it into the same themed SVG checkbox icon used for task list items.

Fields

checked: bool

Whether checkbox is checked.

Emphasis

Emphasis inline container.

Strong

Strong emphasis inline container.

StrongEmphasis

Combined strong+emphasis, e.g. ***text*** or ___text___.

This is parsed as a single inline node to avoid leaving dangling delimiters that would otherwise be treated as plain text.

Strikethrough

Strikethrough (extension), e.g. ~~text~~.

Mark

Highlight/mark (extension), e.g. ==text==.

Superscript

Superscript (extension), e.g. ^text^.

Subscript

Subscript (extension), e.g. ~text~.

Link

Inline link node.

Fields

url: String

Link destination URL.

title: Option<String>

Optional link title.

LinkReference

Reference-style link placeholder (CommonMark): [text][label], [label][], [label].

These cannot be fully resolved during inline parsing because reference definitions may appear later in the document. The top-level parse() performs a post-processing pass that converts this into a Link when a matching definition exists in Document.references.

If no matching definition is found, this should be rendered as literal bracketed text (preserving the already-parsed children for the first bracketed segment).

Fields

label: String

Label used for reference resolution (will be normalized when looked up).

suffix: String

Extra literal suffix after the first ] (e.g. "[]" or "[label]"). Empty for shortcut reference links.

FootnoteReference

GFM-style footnote reference (extension), e.g. [^label].

Rendering convention:

• If a matching FootnoteDefinition exists, this renders as a numbered superscript link.
• Otherwise it should fall back to literal text.

Fields

label: String

Referenced footnote label.

Image

Inline image node.

Fields

url: String

Image source URL.

alt: String

Image alt text.

CodeSpan(String)

Inline code span.

InlineHtml(String)

Inline HTML fragment.

HardBreak

Hard line break (two spaces + newline or backslash + newline).

SoftBreak

Soft line break.

PlatformMention

Extended user mentions.

Syntax:

• @username[platform]
• @username[platform](Display Name)

Rendering policy:

• The renderer may convert this to an external profile link based on a platform mapping table.

Fields

username: String

Platform username/handle.

platform: String

Platform key, for example github.

display: Option<String>

Optional display label override.

InlineMath

Inline math (LaTeX), e.g. $E = mc^2$.

Rendering policy:

• Rendered using KaTeX in inline mode.
• Content is raw LaTeX source code.

Fields

content: String

Raw inline LaTeX content.

DisplayMath

Display math (LaTeX), e.g. $$\int_0^\infty e^{-x^2} dx$$.

Rendering policy:

• Rendered using KaTeX in display mode.
• Content is raw LaTeX source code.

Fields

content: String

Raw display LaTeX content.

MermaidDiagram

Mermaid diagram (code block with language=“mermaid”).

Rendering policy:

• Rendered using mermaid-rs-renderer to SVG.
• Content is raw Mermaid diagram source code.

This is created during parsing when a fenced code block has info string “mermaid”.

Fields

content: String

Raw Mermaid diagram source.

Trait Implementations

impl Clone for NodeKind

fn clone(&self) -> NodeKind

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for NodeKind

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.