| string) - Optional - Alias(es) for the language.
### Returns
- **undefined**
```
--------------------------------
### Basic String Literals
Source: https://github.com/wooorm/lowlight/blob/main/test/fixture/rust-strings/output.txt
Demonstrates single-quoted strings with escaped characters like newlines and hex/unicode escapes.
```string
'a';
```
```string
'\n';
```
```string
'\x1A';
```
```string
'\u12AS';
```
```string
'\U1234ASDF';
```
```string
b'a';
```
--------------------------------
### List Registered Languages
Source: https://github.com/wooorm/lowlight/blob/main/readme.md
Lists all programming languages currently registered with the lowlight instance. Initially empty, languages can be registered using `lowlight.register()`.
```javascript
import {createLowlight} from 'lowlight'
import markdown from 'highlight.js/lib/languages/markdown'
const lowlight = createLowlight()
console.log(lowlight.listLanguages()) // => []
lowlight.register({markdown})
console.log(lowlight.listLanguages()) // => ['markdown']
```
--------------------------------
### Convert to React/JSX with hast-util-to-jsx-runtime
Source: https://context7.com/wooorm/lowlight/llms.txt
Transforms a hast tree into React components. Compatible with Preact, Solid, Vue, and Svelte by adjusting the runtime imports.
```javascript
import {toJsxRuntime} from 'hast-util-to-jsx-runtime'
import {Fragment, jsx, jsxs} from 'react/jsx-runtime'
import {common, createLowlight} from 'lowlight'
const lowlight = createLowlight(common)
// Highlight code
const tree = lowlight.highlight('typescript', `
interface User {
id: number;
name: string;
}
const user: User = { id: 1, name: 'Alice' };
`)
// Convert to React element
const reactElement = toJsxRuntime(tree, {Fragment, jsx, jsxs})
// Use in a React component
function CodeBlock({language, code}) {
const tree = lowlight.highlight(language, code)
return (
{toJsxRuntime(tree, {Fragment, jsx, jsxs})}
)
}
// For Preact, use preact/jsx-runtime instead
// import {Fragment, jsx, jsxs} from 'preact/jsx-runtime'
// Example component usage
//
```
--------------------------------
### Declare variables in lowlight
Source: https://github.com/wooorm/lowlight/blob/main/test/fixture/rust-variables/output.txt
Syntax for declaring various variable types.
```javascript
let foo;
let mut bar;
let _foo_bar;
```
--------------------------------
### Serialize HAST as HTML
Source: https://github.com/wooorm/lowlight/blob/main/readme.md
Serializes a HAST (Hypertext Abstract Syntax Tree) generated by lowlight into an HTML string using `hast-util-to-html`. This is useful for rendering highlighted code in web pages.
```javascript
import {common, createLowlight} from 'lowlight'
import {toHtml} from 'hast-util-to-html'
const lowlight = createLowlight(common)
const tree = lowlight.highlight('js', '"use strict";')
console.log(toHtml(tree))
```
--------------------------------
### Register Language Grammar
Source: https://github.com/wooorm/lowlight/blob/main/readme.md
Registers a new programming language grammar with the lowlight instance. This allows highlighting code in that language. Can register a single grammar or multiple grammars.
```javascript
import {createLowlight} from 'lowlight'
import xml from 'highlight.js/lib/languages/xml'
const lowlight = createLowlight()
lowlight.register({xml})
// Note: `html` is an alias for `xml`.
console.log(lowlight.highlight('html', 'Emphasis'))
```
--------------------------------
### Define a standard heredoc in Ruby
Source: https://github.com/wooorm/lowlight/blob/main/test/fixture/ruby-heredoc/input.txt
Uses the <<-HTML syntax to define a multi-line string that preserves indentation.
```ruby
def foo()
msg = <<-HTML
#{bar}
HTML
end
```
--------------------------------
### Define Functions Returning Null or True
Source: https://github.com/wooorm/lowlight/blob/main/test/fixture/coffee-function/input.txt
Simple function definitions that return null or true. Useful for basic test cases or placeholder functions.
```javascript
returnNull = -> null
```
```javascript
returnTrue = () -> true
```
--------------------------------
### Define a squiggly heredoc in Ruby
Source: https://github.com/wooorm/lowlight/blob/main/test/fixture/ruby-heredoc/input.txt
Uses the <<~FOO syntax to define a multi-line string that strips leading whitespace based on the indentation of the closing delimiter.
```ruby
def baz()
msg = <<~FOO
#{bar}
FOO
end
```
--------------------------------
### POST /task
Source: https://github.com/wooorm/lowlight/blob/main/test/fixture/http-default/input.txt
Creates or updates a task with the specified ID and status. The extended field can be used for additional options.
```APIDOC
## POST /task
### Description
Creates or updates a task with the specified ID and status. The extended field can be used for additional options.
### Method
POST
### Endpoint
/task
### Query Parameters
- **id** (integer) - Required - The unique identifier for the task.
### Request Body
- **status** (string) - Required - The current status of the task (e.g., "ok").
- **extended** (boolean) - Optional - Indicates if extended options should be applied.
### Request Example
```json
{
"status": "ok",
"extended": true
}
```
### Response
#### Success Response (200)
- **message** (string) - A confirmation message indicating the task was updated.
#### Response Example
```json
{
"message": "Task updated successfully."
}
```
```
--------------------------------
### Register Language Aliases with lowlight.registerAlias
Source: https://context7.com/wooorm/lowlight/llms.txt
Defines alternative names for registered languages. Aliases can be used interchangeably with the primary language name during highlighting.
```javascript
import {createLowlight} from 'lowlight'
import javascript from 'highlight.js/lib/languages/javascript'
import markdown from 'highlight.js/lib/languages/markdown'
import typescript from 'highlight.js/lib/languages/typescript'
const lowlight = createLowlight({javascript, markdown, typescript})
// Register single alias
lowlight.registerAlias('javascript', 'es6')
// Register multiple aliases for one language
lowlight.registerAlias('markdown', ['mdown', 'mkdn', 'mdwn', 'md'])
// Register aliases for multiple languages at once
lowlight.registerAlias({
typescript: ['ts', 'tsx'],
javascript: ['js', 'jsx', 'node']
})
// All aliases now work for highlighting
const tree1 = lowlight.highlight('es6', 'const x = 42')
console.log(tree1.data.language) // Output: 'es6'
const tree2 = lowlight.highlight('mdown', '# Heading')
console.log(tree2.data.language) // Output: 'mdown'
const tree3 = lowlight.highlight('ts', 'const x: number = 42')
console.log(tree3.data.language) // Output: 'ts'
```
--------------------------------
### lowlight.registered - Check If Language Is Registered
Source: https://context7.com/wooorm/lowlight/llms.txt
Checks whether a language name or alias is registered in the lowlight instance.
```APIDOC
## lowlight.registered - Check If Language Is Registered
### Description
Checks whether a language name or alias is registered in the lowlight instance.
### Method
`registered(name: string): boolean
### Parameters
#### Path Parameters
None
#### Query Parameters
None
#### Request Body
None
### Request Example
```javascript
import {createLowlight} from 'lowlight'
import javascript from 'highlight.js/lib/languages/javascript'
const lowlight = createLowlight({javascript})
console.log(lowlight.registered('javascript')) // Output: true
console.log(lowlight.registered('js')) // Output: true (if 'js' is an alias)
console.log(lowlight.registered('python')) // Output: false
```
### Response
- **boolean** (boolean) - Returns `true` if the language or alias is registered, `false` otherwise.
#### Success Response (200)
- **boolean** (boolean) - `true` or `false`
#### Response Example
```json
true
```
```
--------------------------------
### Auto-Detect Language and Highlight Code
Source: https://context7.com/wooorm/lowlight/llms.txt
Automatically detect the programming language and highlight the code. Useful when the language is unknown. Detection can be restricted to a subset of languages, and custom class prefixes can be used.
```javascript
import {common, createLowlight} from 'lowlight'
const lowlight = createLowlight(common)
// Auto-detect language
const result = lowlight.highlightAuto('console.log("Hello, World!");')
console.log(result.data)
// Output: { language: 'javascript', relevance: 5 }
// Restrict detection to specific languages
const restrictedResult = lowlight.highlightAuto(
'SELECT * FROM users WHERE id = 1',
{subset: ['sql', 'javascript', 'python']}
)
console.log(restrictedResult.data)
// Output: { language: 'sql', relevance: 2 }
// Use custom class prefix with auto-detection
const customResult = lowlight.highlightAuto(
'fn main() { println!("Hello"); }',
{prefix: 'syntax-', subset: ['rust', 'go', 'c']}
)
console.log(customResult.data.language)
// Output: 'rust'
```
--------------------------------
### Convert HAST to JSX Runtime
Source: https://github.com/wooorm/lowlight/blob/main/readme.md
Converts a HAST tree generated by lowlight into nodes compatible with JSX runtimes (like React, Preact, etc.) using `hast-util-to-jsx-runtime`. This enables rendering highlighted code within JSX applications.
```javascript
import {toJsxRuntime} from 'hast-util-to-jsx-runtime'
// @ts-expect-error: react types don’t type these.
import {Fragment, jsx, jsxs} from 'react/jsx-runtime'
import {common, createLowlight} from 'lowlight'
const lowlight = createLowlight(common)
const tree = lowlight.highlight('js', '"use strict";')
console.log(toJsxRuntime(tree, {Fragment, jsx, jsxs}))
```
--------------------------------
### Define Multi-line Strings with Ruby Heredocs
Source: https://github.com/wooorm/lowlight/blob/main/test/fixture/ruby-heredoc/output.txt
Uses standard and squiggly heredoc syntax to define multi-line strings containing interpolated variables.
```ruby
def foo()
msg = <<-HTML
#{bar}
HTML
end
```
```ruby
def baz()
msg = <<~FOO
#{bar}
FOO
end
```
--------------------------------
### Define Infix Operators
Source: https://github.com/wooorm/lowlight/blob/main/test/fixture/haskell-infix/output.txt
Define custom infix operators with specified precedence and associativity. Useful for creating domain-specific languages or extending existing ones.
```rust
infix 3 `foo`
infixl 6 `bar`
infixr 9 `baz`
```
--------------------------------
### List Registered Languages with lowlight.listLanguages
Source: https://context7.com/wooorm/lowlight/llms.txt
Retrieves an array of all registered language names. Note that this method does not include aliases in the returned list.
```javascript
import {createLowlight, common, all} from 'lowlight'
// Empty instance has no languages
const emptyLowlight = createLowlight()
console.log(emptyLowlight.listLanguages())
// Output: []
// Common bundle includes 37 languages
const commonLowlight = createLowlight(common)
console.log(commonLowlight.listLanguages().length)
// Output: 37
console.log(commonLowlight.listLanguages().slice(0, 10))
// Output: ['arduino', 'bash', 'c', 'cpp', 'csharp', 'css', 'diff', 'go', 'graphql', 'ini']
// All bundle includes 190+ languages
const allLowlight = createLowlight(all)
console.log(allLowlight.listLanguages().length)
// Output: 197 (or similar, depends on highlight.js version)
// Custom instance
import javascript from 'highlight.js/lib/languages/javascript'
import css from 'highlight.js/lib/languages/css'
const customLowlight = createLowlight({javascript, css})
console.log(customLowlight.listLanguages())
// Output: ['javascript', 'css']
```
--------------------------------
### POST /task
Source: https://github.com/wooorm/lowlight/blob/main/test/fixture/http-default/output.txt
Updates or creates a task status based on the provided ID.
```APIDOC
## POST /task
### Description
Updates the status of a task identified by the provided query parameter.
### Method
POST
### Endpoint
/task
### Parameters
#### Query Parameters
- **id** (string) - Required - The unique identifier of the task.
### Request Body
- **status** (string) - Required - The status of the task.
- **extended** (boolean) - Required - Flag indicating if the task is extended.
### Request Example
{
"status": "ok",
"extended": true
}
### Response
#### Success Response (200)
- **status** (string) - The status of the operation.
- **extended** (boolean) - The extended status of the task.
```
--------------------------------
### Define Swift Class
Source: https://github.com/wooorm/lowlight/blob/main/test/fixture/swift-functions/output.txt
Use this to define a class with a method that returns a boolean.
```swift
class MyClass {
func f() {
return true
}
}
```
--------------------------------
### PL/pgSQL Function to Generate Day Abbreviations
Source: https://github.com/wooorm/lowlight/blob/main/test/fixture/pgsql-default/input.txt
A PL/pgSQL function that returns a set of text, generating day abbreviations for a specified range of Julian days.
```plpgsql
CREATE FUNCTION days_of_week() RETURNS SETOF text AS $$
BEGIN
FOR i IN 7 .. 13 LOOP
RETURN NEXT to_char(to_date(i::text,'J'),'TMDy');
END LOOP;
END;
$$ STABLE LANGUAGE plpgsql;
```
--------------------------------
### Define Module Exports in underscore.js
Source: https://github.com/wooorm/lowlight/blob/main/test/fixture/js-modules/output.txt
Defines default and named exports for utility functions.
```javascript
//------ underscore.js ------
export default function (obj) {};
export function each(obj, iterator, context) {};
export { each as forEach };
export function something() {};
```
--------------------------------
### Highlight.js Multiple Escape Characters
Source: https://github.com/wooorm/lowlight/blob/main/test/fixture/haskell-nested-comments/lisp-mec/output.txt
Demonstrates the use of multiple escape characters in Highlight.js, as discussed in issue 615. This pattern handles spaces and newlines within quoted strings.
```regex
; MEC: Multiple Escape Characters. See https://github.com/isagalaev/highlight.js/issues/615
(|spaces and
newlines|) x
```
```regex
(x) '|quoted|'
```
--------------------------------
### Highlight Auto Code
Source: https://github.com/wooorm/lowlight/blob/main/readme.md
Automatically detects and highlights the programming language of a given string. Requires common languages to be loaded.
```javascript
import {common, createLowlight} from 'lowlight'
const lowlight = createLowlight(common)
console.log(lowlight.highlightAuto('"hello, " + name + "!"'))
```
--------------------------------
### Highlight Code with Known Language
Source: https://context7.com/wooorm/lowlight/llms.txt
Highlight code when the programming language is known. Returns a HAST root node with language and relevance data. Custom class prefixes can be used.
```javascript
import {common, createLowlight} from 'lowlight'
const lowlight = createLowlight(common)
// Highlight JavaScript code
const jsTree = lowlight.highlight('javascript', 'const greeting = "Hello, World!";')
console.dir(jsTree, {depth: null})
// Output:
// {
// type: 'root',
// children: [
// {
// type: 'element',
// tagName: 'span',
// properties: { className: ['hljs-keyword'] },
// children: [{ type: 'text', value: 'const' }]
// },
// { type: 'text', value: ' greeting = ' },
// {
// type: 'element',
// tagName: 'span',
// properties: { className: ['hljs-string'] },
// children: [{ type: 'text', value: '"Hello, World!"' }]
// },
// { type: 'text', value: ';' }
// ],
// data: { language: 'javascript', relevance: 2 }
// }
// Highlight CSS code
const cssTree = lowlight.highlight('css', 'em { color: red }')
console.log(cssTree.data)
// Output: { language: 'css', relevance: 3 }
// Use custom class prefix instead of default 'hljs-'
const customTree = lowlight.highlight('python', 'print("Hello")', {prefix: 'code-'})
// Classes will be 'code-built_in' instead of 'hljs-built_in'
```
--------------------------------
### Default and Named Exports in Underscore.js
Source: https://github.com/wooorm/lowlight/blob/main/test/fixture/js-modules/input.txt
Defines default and named exports for utility functions in a JavaScript module. Use this for defining module interfaces.
```javascript
export default function (obj) {};
```
```javascript
export function each(obj, iterator, context) {};
```
```javascript
export { each as forEach };
```
```javascript
export function something() {};
```
--------------------------------
### Bash command to view last 10 lines of a log file
Source: https://github.com/wooorm/lowlight/blob/main/test/fixture/bash-no-numbers/input.txt
This command is used to display the last 10 lines of the access.log file. Numbers are not highlighted in bash as their semantics are not strictly defined for command line parameters.
```bash
$ tail -10 access.log
```
--------------------------------
### HTTP POST Request with JSON Body
Source: https://github.com/wooorm/lowlight/blob/main/test/fixture/http-default/output.txt
A standard HTTP POST request structure including headers and a JSON-formatted body.
```http
POST /task?id=1 HTTP/1.1
Host: example.org
Content-Type: application/json; charset=utf-8
Content-Length: 19
{"status": "ok", "extended": true}
```
--------------------------------
### lowlight.listLanguages - List Registered Languages
Source: https://context7.com/wooorm/lowlight/llms.txt
Returns an array of all registered language names (not including aliases).
```APIDOC
## lowlight.listLanguages - List Registered Languages
### Description
Returns an array of all registered language names (not including aliases).
### Method
`listLanguages(): string[]
### Parameters
#### Path Parameters
None
#### Query Parameters
None
#### Request Body
None
### Request Example
```javascript
import {createLowlight, common} from 'lowlight'
const lowlight = createLowlight(common)
console.log(lowlight.listLanguages())
// Output: ['arduino', 'bash', 'c', 'cpp', ...]
```
### Response
- **array** (string[]) - An array of registered language names.
#### Success Response (200)
- **array** (string[]) - Array of language names.
#### Response Example
```json
["javascript", "css", "xml"]
```
```