docs: function emphasis(node) {
    var marker = this.options.emphasis
    var content = this.all(node).join('')
  
    // When in pedantic mode, prevent using underscore as the marker when there
    // are underscores in the content.
    if (
      this.options.pedantic &&
      marker === underscore &&
      content.indexOf(marker) !== -1
    ) {
      marker = asterisk
    }
  
    return marker + content + marker
  }