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Re:React: Mixins Considered Harmful by danabramov on Wednesday July 13, 2016 @01:56PM (#12088232)
>It doesn't fare well that a framework that is only 3 years old already has an extensive list of anti-patterns and tons of statements on what not to do.

Doesn’t programming in general have solutions that scale well, and solutions that don’t scale well? Would you rather not have people writing about their experiences because it “doesn’t fare well”?

We are just sharing some things that worked well for us, and some things that didn’t. Things that didn’t (mixins) will eventually be forgotten as we move away from those APIs. So it looks like progress to me, but maybe I misunderstand something.

>Also having to do manual performance optimizations using the framework is a hassle to application developers and can be a major pitfall

You don’t “have to” do those optimizations. We only use them in about one in twenty components. But they are handy, and having an option to speed up a component with a few lines is better than having no such option. What do you think?

Re:React: Mixins Considered Harmful by daliwali on Wednesday July 13, 2016 @02:35PM (#12088552)
A corollary to what I'm saying is that the design patterns that are espoused by React authors can be eliminated by using another abstraction, they're specific to React and have nothing to do with programming in general. I wouldn't go so far as to say, never use mixins in JavaScript, for example.

>You don’t “have to” do those optimizations.

Sure, but it seems to be a trade off of complexity for user experience. It's just covering up a leaky abstraction.

Re:React: Mixins Considered Harmful by danabramov on Wednesday July 13, 2016 @03:22PM (#12088893)
>they're specific to React and have nothing to do with programming in general

Higher-order functions are extremely common and useful in all functional languages. In fact many people gave us the exact opposite feedback: React taught them many functional programming patterns that they later used elsewhere, both with and without JavaScript, not to say React.

>I wouldn't go so far as to say, never use mixins in JavaScript, for example.

This is not what the article says. There is a paragraph clarifying this specific point, as the sibling comment points out. And the article is sprinkled with “in React codebases” and “in our experience” for this very reason.

>Sure, but it seems to be a trade off of complexity for user experience.

I don’t understand what you mean. In most cases you don’t need to do anything, React is fast. When you have an especially complex tree (not very common), you can add three lines to a few files, and React is even faster. It is a tradeoff, and it is a pretty damn good tradeoff in my experience working on React apps. What am I missing?

Re:React: Mixins Considered Harmful by daliwali on Wednesday July 13, 2016 @04:03PM (#12089195)
>Higher-order functions are extremely common and useful in all functional languages.

Yes but higher order components as you call them, seem to be an abstraction that you would only use because the base unit of organization is a React component. I'm of the opinion that design patterns emerge due to deficiencies in the language or abstraction level, and that they can be avoided.

Re:React: Mixins Considered Harmful by danabramov on Wednesday July 13, 2016 @04:13PM (#12089282)
>Yes but higher order components as you call them, seem to be an abstraction that you would only use because the base unit of organization is a React component.

I don’t really see the issue here. “How do you parameterize Y by X?” “Create a function that takes X and returns Y.” Doesn’t really seem React-specific.

The unit of organization is indeed the component. Again, I’m not sure I understand why it being a first-class thing indicates a deficiency. By this logic, functions are deficient in JavaScript because you can pass a function to [].map(), or Promises are deficient because you can resolve() a Promise to another Promise.

I think the opposite is true. The abstractions are more powerful when they afford building higher level abstractions on top of them. Obviously you shouldn’t overuse this, just like you shouldn’t overuse higher order functions, but it’s a nice property to have.

Re:React: Mixins Considered Harmful by daliwali on Wednesday July 13, 2016 @05:45PM (#12089917)
>“How do you parameterize Y by X?” “Create a function that takes X and returns Y.” Doesn’t really seem React-specific.

I'm not talking about the what, but why would anyone think of using higher order functions to build user interfaces in the first place. It complicates the use case: building and mutating DOM Nodes.

>I think the opposite is true. The abstractions are more powerful when they afford building higher level abstractions on top of them.

And what may I ask requires so much power for building web front-ends?

Re:React: Mixins Considered Harmful by danabramov on Thursday July 14, 2016 @09:18AM (#12093453)
>I'm not talking about the what, but why would anyone think of using higher order functions to build user interfaces in the first place. It complicates the use case: building and mutating DOM Nodes.

Why are you using a higher order function to `[].filter()` an array? It complicates the use case: iterating over items.

>And what may I ask requires so much power for building web front-ends?

I don’t know what kind of apps you are building, but use cases for React at Facebook are very complex. You may create an Ads account and go through the ad campaign creation flow to see what I mean.

Re:React: Mixins Considered Harmful by pka on Wednesday July 13, 2016 @07:49PM (#12090662)
Higher order functions are not such a complicated concept. Just a function passed to a function.

You use functions, right?

Re:React: Mixins Considered Harmful by daliwali on Thursday July 14, 2016 @03:13AM (#12092148)
Yes, but why is the question. I think that is seriously not given much thought and people just accept man-made complexity as essential. It seems tautological to say that higher order components extend components, but it is only due to the design decisions of the React authors that application code must fit its own paradigm, not the other way around.
Re:React: Mixins Considered Harmful by pka on Thursday July 14, 2016 @04:01PM (#12096779)
On the contrary, it's about reducing complexity. You don't have to worry about mixins, classes, prototypes, inhertiance. Just plain old functions. Can't get simpler than that.
Re:React: Mixins Considered Harmful by jhall1468 on Wednesday July 13, 2016 @03:16PM (#12088858)
> they're specific to React and have nothing to do with programming in general.

I can't think of a single design pattern used in React that isn't a highly common design pattern in any number of languages.

HOC's are just a React implementation of Higher-order Functions.

> I wouldn't go so far as to say, never use mixins in JavaScript, for example.

Neither did they...

This doesn’t mean that mixins themselves are bad. People successfully employ them in different languages and paradigms, including some functional languages... Nevertheless, we think that mixins are unnecessary and problematic in React codebases.