ref: 7ed22e9fb6a5b74c52ae6054b843b8c64e83f4b6
dir: /tpl/tplimpl/embedded/templates/shortcodes/param.html/
{{- $name := (.Get 0) -}}
{{- with $name -}}
{{- with ($.Page.Param .) }}{{ . }}{{ else }}{{ errorf "Param %q not found: %s" $name $.Position }}{{ end -}}
{{- else }}{{ errorf "Missing param key: %s" $.Position }}{{ end -}}