text: import { visit } from 'unist-util-visit'
  import { slug } from 'github-slugger'
  import { toString } from 'hast-util-to-string'
  
  export default function remarkTocHeadings(options) {
    return (tree) =>
      visit(tree, 'heading', (node, index, parent) => {
        const textContent = toString(node)
        options.exportRef.push({
          value: textContent,
          url: '#' + slug(textContent),
          depth: node.depth,
        })
      })
  }
  