2008年9月30日 · Class. When you define a class, you define a blueprint for a data type. class hold data, have method that interact with that data and are used to instantiate objects. Module. Modules are a way of grouping together methods, classes, and constants. Modules give you two major benefits: => Modules provide a namespace and prevent name clashes.

2016年2月25日 · A = Class.new B = Class.new A a, b = A.new, B.new b.class < A # true - means that b.class is a subclass of A a.class < B # false - means that a.class is not a subclass of A # Another possibility: Use #ancestors b.class.ancestors.include? A # true - means that b.class has A among its ancestors a.class.ancestors.include?

2011年4月28日 · You can't use any of Ruby's keywords as variable names, so you won't be able to have variables named def or module or if or end, etc - class is no different. For example, consider the following: def show_methods(class) puts Object.const_get(class).methods.inspect end show_methods "Kernel"

2010年6月10日 · In Ruby, everything is exposed and everything can be modified from anywhere else. If you're worried about the fact that classes can be changed from outside the "class definition", then Ruby probably isn't for you. On the other hand, if you're frustrated by Java's classes being locked down, then Ruby is probably what you're looking for.

2011年5月5日 · As Phrogz mentions in the comments, it's a common idiom in Ruby to track class-level data with an instance variable on the class itself. This can be a tricky subject to wrap your mind around, and there is plenty of additional reading on the subject, but think about it as modifying the Class class, but only the instance of the Class class you're ...

2016年9月29日 · Ruby has some built-in methods to create simple accessor methods for you. If you will use an instance variable on the class (instead of a class variable): class TestClass @variable = "var" class << self attr_accessor :variable end end Ruby on Rails offers a convenience method specifically for class variables:

2015年7月21日 · According to the documentation, Class.new. Creates a new anonymous (unnamed) class with the given superclass (or Object if no parameter is given). Furthermore, You can give a class a name by assigning the class object to a constant. Sheep is that constant, so your code is equivalent to: module Fence class Sheep def speak "Bah." end end end

Keeping classes in modules is perfectly acceptable. To put a class in a separate file, just define the class as usual and then in the file where you wish to use the class, simply put require 'name_of_file_with_class' at the top. For instance, if I defined class Foo in foo.rb, in bar.rb I would have the line require 'foo'.

@Pan, you are confusing Java inner classes and namespaced Ruby classes. A non-static Java nested class is called an inner class and it exists only within an instance of the outer class. There is a hidden field that allows outward references. The Ruby inner class is simply namespaced and is not "bound" to the enclosing class in any way.

A ruby class would take 8 lines to be defined with all the necessary attributes accessors and constructor method and the Struct only take you one line of code After assigning a Struct to a variable I can get and set values using Hash-like subscript syntax and inside it, I can use symbols or strings interchangeably as keys