mdast-util-slice-markdown

Extract portions of Markdown AST trees with configurable behavior for partially included elements.

Installation

npm install mdast-util-slice-markdown

API

sliceMarkdown(tree, start, end, options?)

Extracts a portion of a markdown AST based on character positions.

• tree - The markdown AST node
• start - Starting character position (inclusive)
• end - Ending character position (exclusive)
• options - Configuration object

Configuration

Behavior Options

Control how partially included elements are handled:

{
  behavior: {
    // Formatting elements
    emphasis: 'preserve' | 'trim' | 'exclude' | 'content',    // *italic*
    strong: 'preserve' | 'trim' | 'exclude' | 'content',      // **bold**
    link: 'preserve' | 'trim' | 'exclude' | 'content',        // [text](url)
    
    // Code elements  
    inlineCode: 'preserve' | 'trim' | 'exclude',              // `code`
    code: 'preserve' | 'trim' | 'exclude',                    // ```blocks```
    
    // Media elements
    image: 'preserve' | 'trim' | 'exclude'                    // ![alt](src)
  }
}

Behavior Types:

• preserve - Keep the element with its formatting
• trim - Keep text content, trim sliced
• exclude - Remove the element entirely
• content - Extract visible content (for links)

Other Options

{
  preserveBlocks: true,        // Keep empty blocks after slicing
  trimWhitespace: false,       // Trim whitespace at boundaries
  handlers: {}                 // Custom node handlers
}