{{- $date := . -}}
{{- $extraClass := slice -}}
{{ if reflect.IsSlice . -}}{{ $date = index . 0 }}{{ $extraClass = index . 1 }}{{ end -}}
<time class="{{ with $extraClass }}{{.}}{{ end }}" timestamp="{{ $date }}" title="{{ time $date | dateFormat "2006-01-02 15:04 MST" }}">{{ partial "year-relative-date.txt" $date }}</time>