问题描述
虽然覆盖了一些分配方法，我发现，如果我使用隐式接收器的field_two方法，首先覆盖的方法，field_one，不会被调用。相反，默认的'field_one ='好像是叫。
While overriding some assignment methods, I discovered that if I use the implicit receiver in the field_two method, the first overridden method, field_one, doesn't get called. Instead, the default 'field_one=' seems to be called.
#controller
def do_something
@something=Something.first
@something.field_two="some_value"
end
class Something<ActiveRecord::Base
def field_one=(value)
puts "hi"
write_attribute(:field_g_five,value)
end
def field_two=(value)
field_one="whatever"
write_attribute(:field_g_one,value)
end
end
不过，如果我改变接收机是明确的，我重写的方法被调用：
However, if I change the receiver to be explicit, my overridden method gets called:
def field_two=(value)
self.field_one="whatever"
write_attribute(:field_g_one,value)
end
什么是怎么回事？
What is going on here?
推荐答案
默认 field_one 是没有得到所谓的，你设置了一个名为本地变量 field_one 里面的方法。
The default field_one isn't getting called, you're setting a local variable called field_one inside the method.
如果你想它明确要调用 field_one 那个类中的方法，您必须$与点$ PFIX它的自我。
If you want to make it explicit that you want to call the field_one method inside that class, you must prefix it with self.
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