How to Access the Parent/Global Pipeline in Go Templates' Range Action?

Accessing Parent/Global Pipeline in Go Templates' Range Action

In Go's text/template package, the ability to access pipelines prior to a range action or the parent/global pipeline is essential. Consider the following example:

const page = `{{range .Files}}<script src="{{html .Path}}/js/{{html .}}"></script>{{end}}`

type scriptFiles struct {
    Path string
    Files []string
}

func main() {
    t := template.New("page")
    t = template.Must(t.Parse(page))

    t.Execute(os.Stdout, &scriptFiles{"/var/www", []string{"go.js", "lang.js"}})
}

In this example, accessing .Path won't be possible within the range action because .dot transforms to the current Files element.

Recommended Solution - Using the $ Variable

According to the text/template package documentation, the $ variable holds the data argument passed to Execute, which is the initial value of .dot. Thus, to access the outer scope's Path using $.Path in the range action, use the following variation:

const page = `{{range .Files}}<script src="{{html $.Path}}/js/{{html .}}"></script>{{end}}`

Alternative Solution - Custom Variable

Prior to the range action, a custom variable can be defined to pass a value into the range scope. For instance:

const page = `{{$p := .Path}}{{range .Files}}<script src="{{html $p}}/js/{{html .}}"></script>{{end}}`

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