Meyer also thought (for a while) that inheritance was more powerful than genericity. Later he admitted his "proof" of that was weak.
If Inheritance is so bad, why does everyone use it?
201–210 of 389 posts
Re: If Inheritance is so bad, why does everyone use it?
#202Nobody calls it this, but cascading styles in CSS is just like inheritance and I think should be avoided for all the same reasons. I feel it's a big part of why CSS at scale becomes unmaintainable. There isn't even a built-in way to compose two classes together if you want to avoid cascading/inheritance. It looks like composition over inheritance has caught on as the better default in other languages, but in the CSS…
The cascade is not much like inheritance at all. If anything it's more like composition because the styles can come from multiple sources, eg user styles vs author styles, multiple layers.
The cascade is so much not like inheritance that I wonder if you meant either the concept of selectors in general, or inherited properties?
Re: If Inheritance is so bad, why does everyone use it?
#203Earlier quoted context omitted.
> For me the main point is (runtime) polymorphism. E.g. you have a function that takes a general type, and you can pass multiple specific types and it will do the right thing. The runtime part is what I dislike. If I have a fruit which is an apple or a banana, I can't pass that to a method expecting an apple or banana. It can only be passed as a fruit. > And if you want to avoid huge if-else statements, you should pu…
> The runtime part is what I dislike. If I have a fruit which is an apple or a banana, I can't pass that to a method expecting an apple or banana. It can only be passed as a fruit. Heh? An apple is a fruit, you can pass it to any place expecting the former. Like, this is Liskov’s substitution’s one half. With generics, you can be even more specific (co/in/contra-variance).
I think GP is talking about something like this:
Fruit* fruit = new Apple();
ConsumeApple(fruit); // Doesn't work; requires Apple*
fruit = new Banana();
ConsumeBanana(fruit); // Doesn't work; requires Banana*
ConsumeFruit(fruit); // Okay, function signature is void(Fruit*)Re: If Inheritance is so bad, why does everyone use it?
#204Oh, darling, strap in because the Hacker News catwalk is serving us a spicy mix of opinions on inheritance in programming! First up, we've got the crowd who treats CSS like it’s the ugly stepchild of inheritance, preaching the gospel of "composition over inheritance" as if it's the latest fashion trend. Then there's the old guard, clutching their pearls and insisting that inheritance isn't the problem—it's just misun…
It's funny how easy it is to spot a ChatGPT reply
Do you think it is because it is too verbose? Long winded?
A human wouldn't bother to write that much?
Re: If Inheritance is so bad, why does everyone use it?
#205Earlier quoted context omitted.
I'm inclined to semi-agree with this, although I'm not sure I'd be quite as adamant about it myself. But I do generally think that CSS is taught in a way that encourages some bad practice around cascade/inheritance. I will point out though that (at least in my experience), BEM solved the majority of these problems for me even without a preprocessor. The language is definitely oriented towards inheritance/cascade, but…
> But I do generally think that CSS is taught in a way that encourages some bad practice around cascade/inheritance. I will point out though that (at least in my experience), BEM solved the majority of these problems for me even without a preprocessor. I think cascading is just a bad default, and I think methodologies like BEM agrees with this by teaching you ways to write CSS in ways that stops cascading from gettin…
But BEM doesn't interact with the cascade. If you have two BEM selectors (or a BEM selector and non-BEM selector) that match an element and set the same property, the cascade algorithm still applies to determine what to set the property to.
Re: If Inheritance is so bad, why does everyone use it?
#206Earlier quoted context omitted.
> But I do generally think that CSS is taught in a way that encourages some bad practice around cascade/inheritance. I will point out though that (at least in my experience), BEM solved the majority of these problems for me even without a preprocessor. I think cascading is just a bad default, and I think methodologies like BEM agrees with this by teaching you ways to write CSS in ways that stops cascading from gettin…
But BEM doesn't interact with the cascade. If you have two BEM selectors (or a BEM selector and non-BEM selector) that match an element and set the same property, the cascade algorithm still applies to determine what to set the property to.
Sure, but the idea with BEM is that you generally don't have situations where the result of that algorithm is confusing or unexpected. Or at least that's been my experience, even on large codebases. I generally don't run into situations where styles overload each other in weird ways when I'm using BEM (others' experiences might vary).
You could throw the same criticism at Tailwind -- Tailwind can still expose you to cascade issues, not all Tailwind classes are single-level selectors under the hood and not all Tailwind classes only target one property. At the end of the day this is all compiling down to raw CSS, so in neither situation have you actually eliminated the cascade. But with both BEM and Tailwind you are much less likely to see those situations, and when they do arise they are less likely to introduce long-term maintenance problems and are more likely to be easy to address/encapsulate. If you run into cascade bugs with Tailwind, it's probably something you fix in like one file, instead of needing to search through five.
BEM doesn't technically interact with anything, it's just a style of writing CSS. There's literally no technology behind it, it is just a naming convention. But in practice, using a naming convention mitigates or eliminates a large number of cascade issues.
Re: If Inheritance is so bad, why does everyone use it?
#207[deleted]
Re: If Inheritance is so bad, why does everyone use it?
#208I feel people don't understand what inheritance and (object orientation in general) is useful for, misuse it, and then it gets a bad reputation. It's not about making nice hierarchies of Cars, Fruits, and Ovals. For me the main point is (runtime) polymorphism. E.g. you have a function that takes a general type, and you can pass multiple specific types and it will do the right thing. And if you want to avoid huge if-e…
> I feel people don't understand ...
> For me ...
Sorry, but right off the bat this is just painting you as an example of "There are N camps, and each camp declares the other camp as wrong."
Yes, that's what inheritance is for you. For others it is something else. Why is your way the one that "correctly understands" it?
The article itself covers this - that some languages have lumped 3 different concepts into one that they call inheritance, leading to the different camps and comments like yours. Your camp is specifically mentioned:
> Abstract data type inheritance is about substitution: this thing behaves in all the ways that thing does and has this behaviour (this is the Liskov substitution principle)
Re: If Inheritance is so bad, why does everyone use it?
#209Nobody calls it this, but cascading styles in CSS is just like inheritance and I think should be avoided for all the same reasons. I feel it's a big part of why CSS at scale becomes unmaintainable. There isn't even a built-in way to compose two classes together if you want to avoid cascading/inheritance. It looks like composition over inheritance has caught on as the better default in other languages, but in the CSS…
The cascade is not much like inheritance at all. If anything it's more like composition because the styles can come from multiple sources, eg user styles vs author styles, multiple layers. The cascade is so much not like inheritance that I wonder if you meant either the concept of selectors in general, or inherited properties?
Yeah, the other poster pointed out https://developer.mozilla.org/en-US/docs/Web/CSS/Inheritance and https://developer.mozilla.org/en-US/docs/Web/CSS/Cascade.
I meant the concept that when you e.g. apply the style "color: blue;" to an element, all child elements get the same style unless you override it. I'm not saying it's identical to inheritance, but it's similar in that changes and additions at the top-level ripple down to lower levels, which I find causes most of the problems when writing maintainable code.
Re: If Inheritance is so bad, why does everyone use it?
#210I feel people don't understand what inheritance and (object orientation in general) is useful for, misuse it, and then it gets a bad reputation. It's not about making nice hierarchies of Cars, Fruits, and Ovals. For me the main point is (runtime) polymorphism. E.g. you have a function that takes a general type, and you can pass multiple specific types and it will do the right thing. And if you want to avoid huge if-e…
I feel people don't understand what inheritance and (object orientation in general) is useful for, misuse it, and then it gets a bad reputation. It's not about making nice hierarchies of Cars, Fruits, and Ovals.
One point to add to yours: well executed OOP allows for "structural" flow of control where the object hierarchy, inheritance, events, and overrides allow for the "structure" of the hierarchy to control the flow of logic.
I wrote two articles on this with concrete examples and use cases:
https://medium.com/codex/structural-control-flow-with-object...
https://medium.com/@chrlschn/weve-been-teaching-object-orien...