func marshalString(tag tag) marshaler {
	formSet := formSetter(tag)
	return func(v reflect.Value, p *Params) error {
		s := v.String()
		if tag.omitempty && s == "" {
			return nil
		}
		formSet(tag.name, v.String(), p)
		return nil
	}
}
// marshalString marshals s string field.
marshalString marshals s string field.
// marshalString marshals s string field .
func marshalString(tag tag) marshaler {
	formSet := formSetter(tag)
	return func(v reflect.Value, p *Params) error {
		s := v.String()
		if tag.omitempty && s == "" {
			return nil
		}
		formSet(tag.name, v.String(), p)
		return nil
	}
}
func marshalString ( tag tag ) marshaler { formSet := formSetter ( tag ) return func ( v reflect . Value , p * Params ) error { s := v . String ( ) if tag . omitempty && s == " " { return nil } formSet ( tag . name , v . String ( ) , p ) return nil } }
marshalString marshals s string field.
marshalString marshals s string field .