爲什麼包含Rescuable模塊不起作用？

Question

class MyKlass 

    include ActiveSupport::Rescuable 

    rescue_from Exception do 
    return "rescued" 
    end 

    #other stuff 
end 

MyKlass是純ruby對象，但在Rails應用程序中定義。

如果我嘗試在rails控制檯中調用MyKlass實例，然後將其應用於該方法，該方法肯定應該引發異常，除了預期將被解救的錯誤之外，沒有任何事情發生。

Answer 1

下面是它應該如何使用：

class MyKlass 
    include ActiveSupport::Rescuable 
    # define a method, which will do something for you, when exception is caught 
    rescue_from Exception, with: :my_rescue 

    def some_method(&block) 
    yield 
    rescue Exception => exception 
    rescue_with_handler(exception) || raise 
    end 

    # do whatever you want with exception, for example, write it to logs 
    def my_rescue(exception) 
    puts "Exception catched! #{exception.class}: #{exception.message}" 
    end 
end 

MyKlass.new.some_method { 0/0 } 
# Exception catched! ZeroDivisionError: divided by 0 
#=> true 

不言而喻，即搶救Exception是一種犯罪行爲。