[tutorials]

ruby_class_tests.rb

class ClassA
    @@class_var1 = 1
    @var1 = -1
    
    class << self
        attr_accessor :attr_var1
        
        def class_method1
            puts "\t#{self.class}.class_method1"
            puts "\t\t@var1: #{@var1}"
        end        
    end
    
    def method1
        puts "\t#{self.class}.method1"
        @var1 = 1
        ClassA.attr_var1 = 1
        puts "\t\t@var1: #{@var1}"
        puts "\t\tClassA.attr_var1: #{ClassA.attr_var1}"
    end
    
    def method2
        puts "\t#{self.class}.method2"
    end
end

class ClassB < ClassA
    attr_accessor :var2, :var3

    class << self
        attr_accessor :var2
    end

    @@class_var2 = 2
    @var2 = -2
    
    def method1
        puts "parent method:"
        super
        
        puts "child method:"
        puts "\t#{self.class}.method1"
        @var2 = 2
        puts "\t\tClassB.var2: #{ClassB.var2}"
        puts "\t\t@var1: #{@var1}"
        puts "\t\t@@class_var1: #{@@class_var1}"
        puts "\t\tClassB.attr_var1: #{ClassB.attr_var1}"
        puts "\t\t@var2: #{@var2}"
        puts "\t\t@@class_var2: #{@@class_var2}"
    end
end

A = ClassA.new
B = ClassB.new

puts "A class:"
A.method1
ClassA.class_method1
A.var1 *= 4
puts "\tA.var1: #{A.var1}"
puts "\tClassA.attr_var1: #{ClassA.attr_var1}"
puts "\tA.instance_variables: #{A.instance_variables}"
puts "\tClassA.instance_variables: #{ClassA.instance_variables}"
puts "\tClassA.class_variables: #{ClassA.class_variables}"
puts
puts "B class:"
B.method1
B.method2
B.var1 *= 5
B.var2 += 6
B.var3 = 7
puts "\tB.var1: #{B.var1}"
puts "\tB.var2: #{B.var2}"
puts "\tB.var3: #{B.var3}"
puts "\tClassB.attr_var1: #{ClassB.attr_var1}"
puts "\tB.instance_variables: #{B.instance_variables}"
puts "\tClassB.instance_variables: #{ClassB.instance_variables}"
puts "\tClassB.class_variables: #{ClassB.class_variables}"