assets/assets.go
func Prefix(prefix string, p AssetPipeline) AssetPipeline {
	if prefix == "" {
		return p
	}

	return &prefixPipeline{
		prefix:        prefix,
		AssetPipeline: p,
	}
}
func Prefix(prefix string, p AssetPipeline) AssetPipeline {
	if prefix == "" {
		return p
	}

	return &prefixPipeline{
		prefix:        prefix,
		AssetPipeline: p,
	}
}
// Prefix returns an AssetPipeline that prefixes URLs with the
// given string