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We have a disagreement about the core of OOP. In English, a simple sentence like "The cat eats the rat" can be broken down as follows: - Cat is the subject nou

We have a disagreement about the core of OOP. In English, a simple sentence like "The cat eats the rat" can be broken down as follows: - Cat is the subject noun - Eats is the verb - Rat is the object noun In object-oriented programming, the subject is most often the programmer, the program, the computer, the user agent, or the user. The object is... the object. The verb is the method. So, imagine the sentence "the customer canceled the order." - Customer is the subject noun - Canceled is the verb - Order is the object noun In OOP style you do not express this as customer.cancel(order) even though that reads aloud left-to-right similarly to English. Instead, you orient the expression around the object. The order is the object noun, and is what is being canceled. Thus, order.cancel(). The subject noun is left implicit, because it is redundant. Nearly every subject noun in a given method (or even system) will be the same programmer, program, computer, user agent, or user. For additional perspectives, I recommend reading Part I of "Object-Oriented Analysis and Design with Applications" (3rd edition) by Grady Booch et. al, and "Object Thinking" by David West. --- That said, I think you're right about the single responsibility principle in this example. A class with too many behaviors should usually be decomposed into multiple classes, with the responsibilities distributed appropriately. However, the object should not be left behavior-less. It must still be an anthropomorphized object that encapsulates whatever data it owns with behavior.

valenterry 2y ago
> So, imagine the sentence "the customer canceled the order." > - Customer is the subject noun And this is wrong. Because the customer did not cancel the order. The customer actually asked for the order to be canceled. And the order was then canceled by "the system". Whatever that system is. And that is the reason why it is not expressed as customer.cancel(order) but rather system.cancel(order, reason = "customer asked for it"). > Thus, order.cancel(). The subject noun is left implicit, because it is redundant. Ah, is that so? Then, I would like you to tell me: what happens if there are two systems (e.g. a legacy system and a new system, or even more systems) and the order needs to be sometimes cancelled in both, or just one of those systems? How does that work now in your world?
- Kerrick 2y ago
  > The customer actually asked for the order to be canceled. This is why many object-oriented programmers prefer to talk about message passing instead of method calling. It is indeed about asking for the order to be canceled, and the order can decide whether to fulfill that request.
  - valenterry 2y ago
    > the order can decide whether to fulfill that request. In my world of thinking, orders don't make decisions. If I go to the business team and say "the order decided to" they'll look at me funny. And for good reasons.
    - Kerrick 2y ago
      Go back and read what I said about subject nouns and object nouns. When converting OO concepts to English for non-programmers, it is indeed confusing to say “the order decided not to”—you say “the order couldn’t be” instead. I highly recommend reading the two books I recommended for further perspective on the topic. OO is predicated not on the idea that data is a bag of dead bits on which operations are performed, but that data is embodied within and encapsulated by anthropomorphic objects with their own behavior. It is possible to get to that world of thinking from where you are now. But it is a different world. A different way of thinking.
      - valenterry 2y ago
        > When converting OO concepts to English for non-programmers, it is indeed confusing to say “the order decided not to”—you say “the order couldn’t be” instead. Passive language like "the order couldn't be" might be fine in some real world situations where I don't care about who caused the action. But in code I do care. Because somewhere in code the action has to be made. And yeah, you can put that logic into the Order entity, but then we are back to square one where "the order made the decision". If we are talking about some event that happend, then sure, "the order was canceled" is perfectly fine. So making an "OrderWasCancelled" (or "OrderWasNotCancelled") object and storing it somewhere is intuitive. But we were talking about the action happening and that is a different thing. Also, just to make that clear, I'm not talking just theoretically here. I started my career during the OOP hype time. I actually read books like head first design patterns and others about OOP. But ultimately, I found it's not productive at all, because it doesn't reflect how most people think - at least from my experience. Therefore, I tend to write my code in the same way that non-technical people think. And it turns out, OOP is very far from that.
mrkeen 2y ago
The comparison to English grammar is unnecessary. I didn't use it in my argument and you said it doesn't work that way either, so when you arrive at > The order is the object noun, and is what is being canceled. Thus, order.cancel() You've just restated the position I argued against, without an argument.

valenterry 2y ago

> So, imagine the sentence "the customer canceled the order." > - Customer is the subject noun And this is wrong. Because the customer did not cancel the order. The customer actually asked for the order to be canceled. And the order was then canceled by "the system". Whatever that system is. And that is the reason why it is not expressed as customer.cancel(order) but rather system.cancel(order, reason = "customer asked for it"). > Thus, order.cancel(). The subject noun is left implicit, because it is redundant. Ah, is that so? Then, I would like you to tell me: what happens if there are two systems (e.g. a legacy system and a new system, or even more systems) and the order needs to be sometimes cancelled in both, or just one of those systems? How does that work now in your world?

Kerrick 2y ago
> The customer actually asked for the order to be canceled. This is why many object-oriented programmers prefer to talk about message passing instead of method calling. It is indeed about asking for the order to be canceled, and the order can decide whether to fulfill that request.
- valenterry 2y ago
  > the order can decide whether to fulfill that request. In my world of thinking, orders don't make decisions. If I go to the business team and say "the order decided to" they'll look at me funny. And for good reasons.
  - Kerrick 2y ago
    Go back and read what I said about subject nouns and object nouns. When converting OO concepts to English for non-programmers, it is indeed confusing to say “the order decided not to”—you say “the order couldn’t be” instead. I highly recommend reading the two books I recommended for further perspective on the topic. OO is predicated not on the idea that data is a bag of dead bits on which operations are performed, but that data is embodied within and encapsulated by anthropomorphic objects with their own behavior. It is possible to get to that world of thinking from where you are now. But it is a different world. A different way of thinking.
    - valenterry 2y ago
      > When converting OO concepts to English for non-programmers, it is indeed confusing to say “the order decided not to”—you say “the order couldn’t be” instead. Passive language like "the order couldn't be" might be fine in some real world situations where I don't care about who caused the action. But in code I do care. Because somewhere in code the action has to be made. And yeah, you can put that logic into the Order entity, but then we are back to square one where "the order made the decision". If we are talking about some event that happend, then sure, "the order was canceled" is perfectly fine. So making an "OrderWasCancelled" (or "OrderWasNotCancelled") object and storing it somewhere is intuitive. But we were talking about the action happening and that is a different thing. Also, just to make that clear, I'm not talking just theoretically here. I started my career during the OOP hype time. I actually read books like head first design patterns and others about OOP. But ultimately, I found it's not productive at all, because it doesn't reflect how most people think - at least from my experience. Therefore, I tend to write my code in the same way that non-technical people think. And it turns out, OOP is very far from that.

mrkeen 2y ago

The comparison to English grammar is unnecessary. I didn't use it in my argument and you said it doesn't work that way either, so when you arrive at > The order is the object noun, and is what is being canceled. Thus, order.cancel() You've just restated the position I argued against, without an argument.