List posts chronological within a day

From Jason Becker json on Slack (07 April 2020):

… here’s a template snippet from my layouts/index.html that will allow your posts to be listed in reverse chronological order by day, but within a day be in chronological order. Which I quite like.

{{ $posts := where site.RegularPages “Type” “post” }}
{{ $grouped := $posts.GroupByDate “2006-01-02” }}
{{ $paginated := (.Paginate ($grouped)) }}
​
{{ range $paginated.PageGroups }}
{{ $thedate := (time .Key) }}
<h1> {{ $thedate.Format “January 02” }}</h1>
  {{ range .Pages.Reverse }}
    {{ if eq .Type “post” }}
      {{ .Render “summary”}}
    {{- end }}
  {{ end }}
{{ end }}