code: func getAsciidocContent(ctx *RenderingContext) []byte {
  	var isAsciidoctor bool
  	path := getAsciidoctorExecPath()
  	if path == "" {
  		path = getAsciidocExecPath()
  		if path == "" {
  			jww.ERROR.Println("asciidoctor / asciidoc not found in $PATH: Please install.\n",
  				"                 Leaving AsciiDoc content unrendered.")
  			return ctx.Content
  		}
  	} else {
  		isAsciidoctor = true
  	}
  
  	jww.INFO.Println("Rendering", ctx.DocumentName, "with", path, "...")
  	args := []string{"--no-header-footer", "--safe"}
  	if isAsciidoctor {
  		// asciidoctor-specific arg to show stack traces on errors
  		args = append(args, "--trace")
  	}
  	args = append(args, "-")
  	return externallyRenderContent(ctx, path, args)
  }
docs: // getAsciidocContent calls asciidoctor or asciidoc as an external helper
  // to convert AsciiDoc content to HTML.