astro/packages/markdown/remark/src/mdast-util-mdxish.ts

import {
  mdxExpressionFromMarkdown,
  mdxExpressionToMarkdown
} from 'mdast-util-mdx-expression'
import {mdxJsxFromMarkdown, mdxJsxToMarkdown} from 'mdast-util-mdx-jsx'

export function mdxFromMarkdown(): any {
  return [mdxExpressionFromMarkdown, mdxJsxFromMarkdown]
}

export function mdxToMarkdown(): any {
  return {
    extensions: [
      mdxExpressionToMarkdown,
      mdxJsxToMarkdown,
    ]
  }
}