mdOutline(markdown)

This returns an object representing the structure of the markdown document according to its headings.

• The object’s keys will be the document’s headings in order.
• The object’s values will be the text of those sections or, if the section has its own headings, a subobject for that portion of the document.
• For a given section that has subheadings, any text that appears before the first subheading is included in an initial _text property for that section.

Example: Suppose the markdown document headings.md contains various headings:

# Section 1

Introduction for section 1

## Section 1.1

Text of section 1.1.

## Section 1.2

Text of section 1.2.

# Section 2

## Section 2.1

Introduction for section 2.1

### Section 2.1.1

Text of section 2.1.1.

The outline of this document looks like:

$ ori Origami.mdOutline headings.md
Section 1:
  _text: Introduction for section 1
  Section 1.1: Text of section 1.1.
  Section 1.2: Text of section 1.2.
Section 2:
  Section 2.1:
    _text: Introduction for section 2.1
    Section 2.1.1: Text of section 2.1.1.

A common use for an outline is to render the outline’s keys as navigation links. For example, the following template converts an outline to a list of links for all the headings:

// Given an outline, return navigation links. If a given heading has
// subheadings, this template calls itself recursively.
(outline) => Tree.indent`
  <ul>
    ${ Tree.map(outline, (content, heading) =>
      heading === "_text"
        ? ""
        : Tree.indent`
          <li>
            <a href="#${ Origami.slug(heading) }">${ heading }</a>
          </li>
          ${ Tree.isMaplike(content) ? headings.ori(content) : "" }
        `
    ) }
  </ul>
`

Applying this to the outline:

$ ori headings.ori Origami.mdOutline headings.md
<ul>
  <li>
    <a href="#section-1">Section 1</a>
  </li>
  <ul>
    <li>
      <a href="#section-1.1">Section 1.1</a>
    </li>
    <li>
      <a href="#section-1.2">Section 1.2</a>
    </li>
  </ul>
  <li>
    <a href="#section-2">Section 2</a>
  </li>
  <ul>
    <li>
      <a href="#section-2.1">Section 2.1</a>
    </li>
    <ul>
      <li>
        <a href="#section-2.1.1">Section 2.1.1</a>
      </li>
    </ul>
  </ul>
</ul>

See also Origami.mdHtml for translating a markdown document to HTML.