record Article, title : String, content : String, date : Time

class TimeRenderer < Crinder::Base(Time)
  field year : Int
  field month : Int
  field day : Int
  field hour : Int, unless: date_only?
  field minute : Int, unless: date_only?
  field second : Int, unless: date_only?

  option date_only? : Bool = false
end

class ArticleRenderer < Crinder::Base(Article)
  field title : String
  field content : String
  field date, with: TimeRenderer, options: {date_only?: true}
end

article = Article.new(title: "Add render with options", content: "You can pass options to the nested renderer.", date: Time.local(2020, 4, 20))
ArticleRenderer.render(article) # => "{\"title\":\"Add render with options\",\"content\":\"You can pass options to the nested renderer.\",\"date\":{\"year\":2020,\"month\":4,\"day\":20}}"