> For AI agents: the complete documentation index is available at /llms.txt, the full documentation bundle is available at /llms-full.txt.

# Syntax Support

This page lists what the default pipeline does with common constructs. **Render** means structured DOM output; **placeholder** means the position is kept but nothing is evaluated; **degrade** means a source card plus a diagnostic; **block** means dangerous content is dropped with a readable hint; **ignore** means it never reaches the body.

With `/expand`, resolvers, `handlers`, or component overrides, output changes. Refer to the dedicated pages for details.

## Combined example

The source below configures no resolvers and covers text, lists, a table, a reference, and the default placeholders:

```tsx preview
import { Wikitext } from "react-wikitext";
import "react-wikitext/styles.css";

const source = `== Text and lists ==
'''Bold''', ''italic'', and an [[internal link|internal link]] keep their structure.

* First item
* Second item

== Table and reference ==
{| class="wikitable"
|-
! Column A !! Column B
|-
| Cell || Content<ref>Example reference</ref>
|}

{{Infobox|title=Template placeholder}}
[[File:Example.png|thumb|File placeholder]]`;

export default function Demo() {
  return <Wikitext source={source} lang="en" />;
}
```

Use the tables to look up a construct; use the example to check the overall output.

## Text and blocks

| Construct                         | Default output                    | Status | Notes                                                   |
| --------------------------------- | --------------------------------- | ------ | ------------------------------------------------------- |
| Paragraphs                        | `<p class="wtr-paragraph">`       | Render | Two or more blank lines split; single newlines collapse |
| `'''bold'''`, `''italic''`        | `<b>`, `<i>`                      | Render | Both produce `<i><b>…</b></i>`                          |
| `== Heading ==`, source `h1`–`h6` | `<h1>`–`<h6 class="wtr-heading">` | Render | Participates in anchors and the TOC                     |
| `----`                            | `<hr class="wtr-hr">`             | Render |                                                         |
| Leading spaces                    | Plain text                        | Render | No preformatted semantics                               |
| `<!-- comment -->`                | No output                         | Ignore |                                                         |
| `[[Category:…]]`                  | Category footer                   | Render | Not in the body; sort keys are hidden                   |
| `__TOC__`, `__NOTOC__`            | TOC control                       | Render | Only affects the TOC                                    |
| `#REDIRECT` on the first line     | Redirect banner                   | Render | Skips the body; does not load the target                |

## Lists and tables

| Construct                   | Default output                        | Status  | Notes                                                              |
| --------------------------- | ------------------------------------- | ------- | ------------------------------------------------------------------ |
| `*`, `#`                    | Nested `<ul>` / `<ol>`                | Render  | Continuation lines join the current item                           |
| `;`, `:`                    | `<dl>` / `<dt>` / `<dd>`              | Render  | Supports `; term : definition` and compact forms                   |
| `{\| … \|}`                 | `<table><caption>…</caption><tbody>…` | Render  | Cells use `<th>` / `<td>`                                          |
| Table, row, cell attributes | Allowlisted attributes                | Render  | `style` keeps a safe subset; event attributes and `id` are dropped |
| `colspan`, `rowspan`        | Logical grid plus filler cells        | Render  | Clamped to the table; fillers carry compat classes                 |
| Nested wikitext tables      | Source card                           | Degrade | The whole table degrades; nested HTML `<table>` works              |
| `data-*` on tables          | Safe values kept                      | Render  | Reserved names such as `data-node-id` are rejected                 |

## Links and media

| Construct                     | Default output                          | Status      | Notes                                           |
| ----------------------------- | --------------------------------------- | ----------- | ----------------------------------------------- |
| `[[Page]]`                    | Non-navigable `<span class="wtr-link">` | Render      | Becomes `<a>` when `resolveLink` returns `href` |
| `[[Page\|label]]`             | Same, label is `label`                  | Render      | Namespace prefixes follow the parse result      |
| `[https://example.com label]` | `<a>` with `rel` and `target`           | Render      | Only `http:`, `https:`, `mailto:`               |
| Bare `https://…`              | `<a>` labelled with the URL             | Render      |                                                 |
| `[https://example.com]`       | `<a>` labelled `[N]`                    | Render      | Numbering is independent of references          |
| `[[File:…]]`                  | `<span>` or `<figure>` placeholder      | Placeholder | `<img>` only after `resolveImage`               |
| `<gallery>`                   | Placeholder set of file labels          | Placeholder | No images are loaded                            |
| `<math>`                      | `<code>` formula source placeholder     | Placeholder | No KaTeX                                        |
| `<imagemap>`                  | Block source card                       | Degrade     | No clickable hotspots                           |

## Templates and functions

| Construct                                      | Default output                                   | Status      | Notes                                                         |
| ---------------------------------------------- | ------------------------------------------------ | ----------- | ------------------------------------------------------------- |
| `{{Template\|…}}`                              | `<details class="wtr-template">` or inline badge | Placeholder | Lists arguments; text comes from `labels.templateNotExpanded` |
| Parser function `{{#if:…}}`                    | Placeholder structure                            | Placeholder | Explicitly marked as not evaluated                            |
| Argument `{{{name\|default}}}`                 | Name and default value                           | Placeholder |                                                               |
| Templates and functions supported by `/expand` | Expanded source is reparsed                      | Render      | Calls kept after a failure still render as placeholders       |
| `#invoke`, Lua, `subst`                        | Source preserved                                 | Placeholder | Not executed; a diagnostic is recorded                        |

Magic words inside templates, functions, and arguments do not affect TOC or category detection.

## HTML and extension tags

| Construct                                         | Default output                                          | Status  | Notes                                                                                                          |
| ------------------------------------------------- | ------------------------------------------------------- | ------- | -------------------------------------------------------------------------------------------------------------- |
| Inline HTML (`b`, `i`, `u`, `span`, `code`, …)    | Corresponding elements                                  | Render  | Attributes are allowlisted                                                                                     |
| Block HTML (`div`, `p`, `blockquote`, …)          | Corresponding elements                                  | Render  | May wrap headings; TOC position follows its block                                                              |
| Void elements (`br`, `wbr`, `hr`)                 | Corresponding elements                                  | Render  |                                                                                                                |
| `meta`, `link`                                    | No output                                               | Ignore  |                                                                                                                |
| `script`, `style`, `iframe`, form controls, `svg` | Escaped text, or a readable hint when blocked           | Block   | The default config does not parse these tags, so source stays text; if configured as HTML, the pair is dropped |
| Unknown but not dangerous tags                    | Source card                                             | Degrade | Not rendered as real elements                                                                                  |
| `<nowiki>`                                        | Plain text                                              | Render  | Links and templates are not parsed                                                                             |
| `<pre>`                                           | Whitespace preserved                                    | Render  |                                                                                                                |
| `<ref>`                                           | `<sup class="reference wtr-ref">` plus grouped endnotes | Render  | Named references are reused; `group` groups; duplicates produce diagnostics                                    |
| `<references>`                                    | Marker                                                  | Render  | The matching group section is moved here; groups without markers stay at the end                               |
| `<syntaxhighlight>`                               | `<pre><code class="language-*">` source                 | Render  | Emits a language class; no syntax highlighting                                                                 |
| Other supported extensions                        | Handled per tag                                         | Render  | `semanticComponents.extension` can override                                                                    |

## Page-level structure

| Structure              | Behavior                                                                                          |
| ---------------------- | ------------------------------------------------------------------------------------------------- |
| Table of contents      | `toc` adjusts the threshold; `__TOC__` sets the position; `__FORCETOC__` forces; `__NOTOC__` wins |
| Reference section      | After the body and before categories by default; `<references/>` sets a group position            |
| Categories             | Collected into `div.catlinks.wtr-categories` at the end                                           |
| Redirect               | First-line `#REDIRECT` renders a banner and skips the body                                        |
| Unknown semantic nodes | Source card plus a diagnostic; the page keeps rendering                                           |

## Verifying behavior

1. Inspect `document.diagnostics` for `stage` and `code`.
2. Use `flattenNodes` from `/ast` to inspect the semantic tree and compare it with the prepared HAST.
3. Use `labels` to distinguish "not evaluated", "blocked", and "unknown structure".
4. Treat `src/` and `tests/` as the source of truth; this page follows default behavior.

See [Rendering behavior](/guide/rendering.md) for details and rationale, and [Security model](/guide/security.md) for blocking rules.