![]() Also, if you don't like how dotiw changes the format of distance_of_time_in_words, use the :vague option to revert to the original format. Leap years are handled fine for the years portion although be aware that Feb 29 does have an effect on the days portion that warrants understanding if that level of detail is needed. Years = (20160229 - 19840229) / 10000 # 32īecause Ruby on Rails is tagged, the dotiw gem overrides the Rails built-in distance_of_times_in_words and provides distance_of_times_in_words_hash which can be used to determine the age. Years = (20140228 - 19840229) / 10000 # 29 - a full year hasn't yet elapsed even though some leap year babies think it has, technically this is the last day of the previous year Years = (today - 20140702) / 10000 # person born today is 0 years old # person born a year ago tomorrow is still only 0 years old # person born this time last year is a 1 year old It's definitely unique in its approach but makes perfect sense when you realise what it does: today = 20140702 # 2 July 2014 ![]() # NOTE: could also use `.strftime('%Y%m%d').to_i` You have learned about classes in Ruby, how to create them & why they’re useful!ĭon’t forget to share this article so more people can enjoy it.This is a conversion of this answer (it's received a lot of votes): # convert dates to yyyymmdd format Attr_accessor, attr_reader, attr_writerītw classes themselves are objects too, at least in Ruby □ Summary.This is only the “tip of the iceberg” when it comes to classes. If you know the class you can find out what methods are available (use Google, ri, or pry), in other words, you can discover what the object can do for you! Learning More Methods are the little engines that make things happen in Ruby. When working with objects in Ruby it’s helpful to know what class an object is made from. You can’t access them outside the class unless you define an attr_accessor. ![]() Instance variables are different from local variables because they start with the symbol. These methods become commands for your objects!Įvery Orange object you create will have access to this squeeze method & that’s one of the benefits of using classes.Īn instance variable is something your class knows. How to Make Ruby Classes More UsefulĬlasses become more useful when you start adding instance methods & instance variables to them. With the Orange class example, every orange object you create has its own weight, country of origin, quality, etc.Īnd of course, it doesn’t have to be all about your favorite fruit, this works for a User class or any other class you want to define. Why create objects?īecause every object you create is different & unique. The process of creating an object is known as “instantiation”, so we say that an object is an “instance” of a class. You can create objects using the new method. The main use of a class is to be a container of methods, instance variables & constants, forming a blueprint from which you can create objects. There are other ways to create a class (like Class.new), but these methods are only useful in special situations. An empty class is not very useful, but you can still create objects from it.We use the class keyword, then the end keyword.Class names start with an uppercase letter.The syntax for creating a class goes like this: class Orange You’re going to learn how to write your own classes so you can start writing OOP code, today. That’s the point of creating classes, they are reusable blueprints for your Ruby application. This class defines what attributes ALL books have in common, like:Įvery individual book is an object & you can make many objects like it thanks to the Book class. Classes are the basic building blocks in Object-Oriented Programming (OOP) & they help you define a blueprint for creating objects.Īn object is an individual “thing”, with its own identity & its own data.Ī Book class could be the blueprint for creating books.
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