Code Rules

These rules ensure proper formatting of code blocks and inline code in markdown documents.

Rules in This Category

• MD040 - Fenced code blocks should have a language specified
• MD014 - Dollar signs used before commands without showing output
• MD031 - Fenced code blocks should be surrounded by blank lines
• MD038 - Spaces inside code span elements
• MD046 - Code block style
• MD048 - Code fence style

Why Code Rules Matter

Proper code formatting:

• Enables syntax highlighting for better readability
• Maintains consistency across code examples
• Improves copy-paste reliability
• Ensures proper rendering in different viewers
• Helps readers identify programming languages quickly

Code Block Styles

Fenced Code Blocks (Recommended)

```javascript
function example() {
    return "Hello, world!";
}
```

Indented Code Blocks

    function example() {
        return "Hello, world!";
    }

Inline Code

Use the `console.log()` function to debug.

Language Specifications

Common language tags for syntax highlighting:

Quick Configuration

# .mdbook-lint.toml

# Configure MD040 - Require language tags
[MD040]
allowed_languages = ["js", "python", "rust", "bash"]

# Configure MD046 - Code block style
[MD046]
style = "fenced"  # Options: "fenced", "indented", "consistent"

# Configure MD048 - Code fence style
[MD048]
style = "backtick"  # Options: "backtick", "tilde", "consistent"

Best Practices

1. Always specify language: Enables syntax highlighting
2. Use fenced blocks: More flexible than indented blocks
3. Surround with blank lines: Improves readability
4. Be consistent: Use the same style throughout
5. Escape special characters: Use backslash when needed

Shell Commands

# Good - shows command without prompt
npm install mdbook-lint

# Avoid - dollar sign without output
$ npm install mdbook-lint

Related Categories

• mdBook Rules - mdBook-specific code requirements
• Whitespace Rules - General spacing rules