code snippets for "Compiler|Interpreter Warnings Are Important Learning Opportunities" post

s1.rb

it "should know about the subscribed method for the correct event" do
    @publisher.subscribe :first_event, method(:first_event_handler)
    subscribed = @publisher.subscribed? :first_event, method(:first_event_handler)
    subscribed.should == true
end

s2.rb

subscribed.should be_true

s3.rb

define_method getter do
    event = instance_variable_get variable
 
    if event == nil
        event = Event.new(symbol.to_s)
        instance_variable_set variable, event
    end
 
    event
end

s4.rb

define_method getter do
    if !instance_variable_defined? variable
        event = Event.new(symbol.to_s)
        instance_variable_set variable, event
    end
     
    instance_variable_get variable
end