read.go
func (v Value) RawString() string {
	x, ok := v.data.(string)
	if !ok {
		return ""
	}
	return x
}
func (v Value) RawString() string {
	x, ok := v.data.(string)
	if !ok {
		return ""
	}
	return x
}
// RawString returns v's string value.
// If v.Kind() != String, RawString returns the empty string.