code-block

Code block

Neko extends fenced code blocks with titles, line numbering, range highlighting, and decorative window chrome.

Basic

```js
const msg = "Hello, world";
console.log(msg);
```

With a title

The first token after the language is interpreted as a title:

```js main.js
console.log("title appears in the block header");
```

Line numbers

A # on its own (or with a title) enables line numbers:

```js #
line 1
line 2
```

```js main.js #
with title and line numbers
```

Highlighted ranges

```js #2-3,5
line 1
line 2   ← highlighted
line 3   ← highlighted
line 4
line 5   ← highlighted
```

To highlight ranges without rendering line numbers, prefix with !:

```js !#2-3
line 1
line 2   ← highlighted, no gutter
line 3   ← highlighted, no gutter
```

Window chrome

```js chrome="mac" main.js
// macOS-style traffic-light header (aliases: chrome="macos", chrome="osx")
```

```js chrome="windows" main.js
// Windows-style title bar
```

Supported languages

Most popular languages are highlighted via highlight.js (C#, JS, TS, Python, Go, Rust, Ruby, Java, Kotlin, Swift, HTML, CSS, JSON, YAML, TOML, XML, Bash, PowerShell, SQL, etc.). Use text or plain for no highlighting.

Tips

• Always specify a language for proper highlighting and a11y.
• Use a title (main.cs, Dockerfile, …) when the language alone is ambiguous.
• Keep individual snippets short. For files included from disk, prefer the code-snippet component.