{{- $text := .Text -}}
{{- $hash := print (truncate 2 "" (sha256 .Page.RelPermalink)) (truncate 2 "" (sha256 $text)) -}}
{{- $id := print "heading:" $hash ":" .Anchor -}}

<h{{ .Level }} id="{{ $id | safeURL }}">
  <a title="{{ $text | safeHTML }}" href="#{{ $id | safeURL }}">
    {{ $text | safeHTML }}
  </a>
</h{{ .Level }}>