Should there be additional information in the AST?

Spec
5

Here’s a really weird edge case that shows why this part would be useful, especially for turning into an AST then back into markdown:

Say you turned this big of markdown into an AST:

_*Hello, world*_

You’d get this:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE CommonMark SYSTEM "CommonMark.dtd">
<document xmlns="http://commonmark.org/xml/1.0">
  <paragraph>
    <emph>
      <emph>
        <text>Hello, world</text>
      </emph>
    </emph>
  </paragraph>
</document>

An ast->markdown converter might spit this out:

**Hello, world**

Resulting in bold rather than italic.