5 ms·

While clojureScript is awesome and gets you to think differently when writing javascript, I think a more interesting thing people should check out it es6 (or ec

While clojureScript is awesome and gets you to think differently when writing javascript, I think a more interesting thing people should check out it es6 (or ecmascript 6, or es 2015, w/e it's called now.). It brings many new things to javascript that people from other languages will be used to...likes the "class" syntax. Right now you can write near 100% es6 standard with a pre-compiler. Most use babel. Soon it will run on all the latest browsers without though, making it far better to write then a language that compiles to JS. JS is nice now, I know I know, just give it a try =p Also, another thing to look at is eithe Facebook's flow or Typescript. It adds some type checking, really great. Especially if you are writing server side in Node.

warfangle 11y ago
'class' is one of the most commonly mentioned but least useful constructs available in ES6. Things that win out over it? Destructured assignment, sane module syntax, arrow functions, true block scope variable declaration, and constants.
- Cshelton 11y ago
  Yes, but people coming from java or c# or something will like it. Despite it being just syntactical sugar. I wasn't about to list out all the benefits of es6, that would take several entire blog posts.
  - jeremiep 11y ago
    I would rather see ES6 with no class support whatsoever and having people learn to code without them instead of adding features to satisfy the lowest common denominator. I've used classes in CoffeeScript and regretted it every single time. Once your web project starts to grow in scale classes quickly become your first pain point. Especially given how functional JS libraries have become nowadays.
    - warfangle 11y ago
      Composition over inheritance wins, so hard. (edit: downvote for a typically well-thought-of idiom, especially with regard to a language like js? .. if you disagree, why not talk about it?)
      - Touche 11y ago
        Classes are unavoidable in JavaScript if you care about performance. Recreating redundant functions inside a closure in performance critical code is a sure way to have slow apps.
        jeremiep 11y ago
        Creating an object and creating a closure both need to allocate memory in the VM, but the closure doesn't need to expose its internals the way an object does and therefore can be further optimized by the runtime. If you need to write performance critical JavaScript, then allocating new objects will be just as slow as creating new closures. In either cases you should allocate them ahead of time and then closures are still the clear winner.
        deleted 11y ago
        [deleted]
        warfangle 11y ago
        > Creating an object and creating a closure both need to allocate memory in the VM, but the closure doesn't need to expose its internals the way an object does and therefore can be further optimized by the runtime. Actually... creating an object instance via a constructor lets the runtime use an internal class, which improves performance (as long as you don't modify its properties post-construction). This is a well-known aspect of V8 performance.
        jeremiep 11y ago
        Even with an internal class you're still doing lookups for properties. A closure can instead use local variables which are accessed by index. Why do you think its good practice to pull properties out of objects and into local variables before a tight loop?
outworlder 11y ago
I think the 'class' keyword is a mistake. People were happily creating class-like constructs before. But the exposed javascript "objects" made it clear it wasn't a traditional "class" found in other languages. Also, how is ES6 more interesting than ClojureScript?
- spion 11y ago
  There is no single "traditional class" in other languages. Pretty much every language has its own flavor of classes with different restrictions and internals.
  - outworlder 11y ago
    Perhaps a better term would be "popular"? As in, what's in use by Java and C#.

warfangle 11y ago

'class' is one of the most commonly mentioned but least useful constructs available in ES6. Things that win out over it? Destructured assignment, sane module syntax, arrow functions, true block scope variable declaration, and constants.

Cshelton 11y ago
Yes, but people coming from java or c# or something will like it. Despite it being just syntactical sugar. I wasn't about to list out all the benefits of es6, that would take several entire blog posts.
- jeremiep 11y ago
  I would rather see ES6 with no class support whatsoever and having people learn to code without them instead of adding features to satisfy the lowest common denominator. I've used classes in CoffeeScript and regretted it every single time. Once your web project starts to grow in scale classes quickly become your first pain point. Especially given how functional JS libraries have become nowadays.
  - warfangle 11y ago
    Composition over inheritance wins, so hard. (edit: downvote for a typically well-thought-of idiom, especially with regard to a language like js? .. if you disagree, why not talk about it?)
    - Touche 11y ago
      Classes are unavoidable in JavaScript if you care about performance. Recreating redundant functions inside a closure in performance critical code is a sure way to have slow apps.
      - jeremiep 11y ago
        Creating an object and creating a closure both need to allocate memory in the VM, but the closure doesn't need to expose its internals the way an object does and therefore can be further optimized by the runtime. If you need to write performance critical JavaScript, then allocating new objects will be just as slow as creating new closures. In either cases you should allocate them ahead of time and then closures are still the clear winner.
        deleted 11y ago
        [deleted]
        warfangle 11y ago
        > Creating an object and creating a closure both need to allocate memory in the VM, but the closure doesn't need to expose its internals the way an object does and therefore can be further optimized by the runtime. Actually... creating an object instance via a constructor lets the runtime use an internal class, which improves performance (as long as you don't modify its properties post-construction). This is a well-known aspect of V8 performance.
        jeremiep 11y ago
        Even with an internal class you're still doing lookups for properties. A closure can instead use local variables which are accessed by index. Why do you think its good practice to pull properties out of objects and into local variables before a tight loop?

outworlder 11y ago

I think the 'class' keyword is a mistake. People were happily creating class-like constructs before. But the exposed javascript "objects" made it clear it wasn't a traditional "class" found in other languages. Also, how is ES6 more interesting than ClojureScript?

spion 11y ago
There is no single "traditional class" in other languages. Pretty much every language has its own flavor of classes with different restrictions and internals.
- outworlder 11y ago
  Perhaps a better term would be "popular"? As in, what's in use by Java and C#.