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Re:Ask HN: Resources for catching up on modern JavaScript fo... by chatmasta on Tuesday April 10, 2018 @09:44AM (#16801268)
I was in a similar position two years ago. Best advice I can give is to just build a full-stack website with JS on front and back. Make sure you get your tooling set up so you can use ES6, and then just focus on building what you want.

I would recommend using create-react-app for frontend as it sets up all the tooling for you and is production ready. On backend, I would recommend parse-server but I just have a personal affection for its batteries-included approach. You could also just use a simple node/express setup (and/or mount parse-server onto it).

Three major things that might trip you up, and you should read about and practice early:

- Async programming / closures. You can't just call a function on an object in a loop like you can in Python.

- Promises. Figure out how to use these instead of callbacks as soon as you can.

- Prototypical inheritance. I recommend explicitly writing "classes" with the "old style" of YourClass.prototype.method before moving to using the "class" keyword. The "class" keyword is just syntactical sugar on prototypical inheritance so it's a good idea to learn the raw form before the sugared form.

Recommended reading:

- "You Don't Know JS" (https://github.com/getify/You-Dont-Know-JS/blob/master/READM...)

- Source code. Read the source code of as many JS projects as you can find.

Re:Ask HN: Resources for catching up on modern JavaScript fo... by sametmax on Tuesday April 10, 2018 @11:36AM (#16802123)
+1 for You Don't Know JS.

But the rest is a bit "all or nothing" isn't it ?

React is a huge bite for a start, espacially since you need webpack. How about something lighter first, like Vue.js ? Once you get how it works, you can up your game and go to React (+ webpack + Mobx, don't try redux at first it's too much) or Angular 2.

As for the backend, you can stay in Python first and do a rest API. Then once you get the front right, write a backend using node AND a framework. Do not attempt to pure JS first, it's like doing web Python without django or flask. Possible, but not worth it. ExpressJS is close to flask in philosophy, except for the asynchronous part.

If you really want to have fun though, checkout crossbar.io.

It's a Python router than allow very easy PUB/SUB and RPC between clients. Clients can be written in JS, Python, Java, C#, etc.

You can even write JS clients in the browser, making push notifications and other real time feature a breeze. It's a good way to give you motivation to try on JS: mix it with what you know, and try a new exciting technology. Plus a good way to see the difference between async in JS and in Python.

Re:Ask HN: Resources for catching up on modern JavaScript fo... by tomc1985 on Tuesday April 10, 2018 @01:11PM (#16803017)
Scratch all that. Go for as long as possible without reaching for a framework like React or Vue. You don't learn JS learning those tools, you are just learning the tool.

React et al gives language newbies good shoulders to stand on, but a lot of React's so-called concepts map fairly simply to lesser-known language primitives. (And for the record, writing a simple, one-way databinding library in JS takes all of about 20 lines of code)

Don't be a tool, learn more than the tools :)

Re:Ask HN: Resources for catching up on modern JavaScript fo... by alibarber on Tuesday April 10, 2018 @01:41PM (#16803314)
This is something that I'm not sure how I feel about in general. I'm not really interested in learning any particular framework (because there seem to be about a billion and the landscape changes every day), but then again re-inventing the wheel over and over is never fun, even if learning something new. I'm hoping that something like React might be quite instructive to use and study in looking at its design choices and API structure - and also to learn _why_ someone might want to use it and what the problems are in JS/Front end development that it's there to solve...
Re:Ask HN: Resources for catching up on modern JavaScript fo... by tomc1985 on Tuesday April 10, 2018 @02:17PM (#16803684)
The thing is, you aren't reinventing the wheel. There is a certain amount of repetition in programming... you will always need to sort a list, or iterate a for loop, or assign a couple of variables.

There is a re-occurring thread of inventors (especially on here) building things that are more complex than necessary, and certainly more complicated than the problem they are working on. React, Angular, Electron, and a lot of other tools all use 1000 words where 100 would do. If you go through programming thinking that that is normal, or acceptable, you are doing more harm to the ecosystem and your own knowledge than if you had "reinvented the wheel" a couple of times on smaller tasks.

In the long run neither frameworks nor languages matter. If programming to you is reaching for the latest framework du-jour then you will find yourself left in the dust unless you keep with technology's futile and arbitrarily-hastened pace. (And no, I do not consider it OK that this is considered necessary) But if you master the concepts of what the tools do... then you start seeing just how badly and inefficiently they are written. Then you find yourself bypassing them, and simultaneously completing projects faster than ever while writing bespoke code that fits your requirements perfectly, and is also much easier to maintain (because hey you wrote it)

Re:Ask HN: Resources for catching up on modern JavaScript fo... by sametmax on Wednesday April 11, 2018 @04:05AM (#16808991)
> In the long run neither frameworks nor languages matter.

While I agree with this statement, a real life project include several people, some new to the projects, some good, some not, some with experience and some young. It requires communication and sharing things.

And tooling helps a lot with that.

Re:Ask HN: Resources for catching up on modern JavaScript fo... by dalai on Tuesday April 10, 2018 @03:10PM (#16804183)
Could you expand a bit on your recommendation? Do you mean just ES6? Do you have specific resources to suggest? What do you think about all the associated tooling for writing, compiling, testing and debugging, when starting? Is a browser and a text editor good enough, or is a minimal setup vital, in particular when one is building something that is more than a toy project?
Re:Ask HN: Resources for catching up on modern JavaScript fo... by l_t on Tuesday April 10, 2018 @04:14PM (#16804868)
I would try to think of it from a first-principles approach. You can begin with a blank slate, for instance, a single HTML file with a <script> tag. Only when "doing it yourself" becomes tedious do you start to look for libraries to solve your problem.

Personally, I find a bare minimum of tooling to be valuable. I have built SPAs using 100% vanilla JS, and it can be quite repetitive and error-prone. I'd recommend using highly simple build tooling (maybe Brunch) and an extremely simple view layer like https://github.com/Matt-Esch/virtual-dom. Pretty much everything else you can build yourself with surprisingly few lines of code -- state management, routing, event handling, data bindings, etc. I think of it as "building your own framework", and although you might not want to do it for every project, the learning experience is great.

Re:Ask HN: Resources for catching up on modern JavaScript fo... by tomc1985 on Tuesday April 10, 2018 @04:46PM (#16805181)
l_t's response was very good, I would recommend what he has to say.

To follow-up... essentially, yes. A text editor and a <script> tag is one way to approach it, though I would advise that you stick with making something small. One-off, toy SPA's are a great way to get to know JS. (Here's a challenge: TodoMVC sans frameworks ==evil grin==) With big ideas it is a lot harder to do this with big ideas until you have a firm layout of the code in your head.

In fact, this may go against a lot of recommendations but I'd recommend getting comfortable with ES5 before moving to ES6. A lot of existing code is written to ES5 standard and, while ES5 is certainly missing LOTS of important goodies, there is more than enough language to do most kinds of data-processing. (Though don't feel bad if you find yourself building a util.js with a bunch of string manipulation functions, for example, or find yourself importing jquery... I consider JQ to be an exception to the 'no tooling' rule, because classic JS DOM manip really, really sucks). Things like callback hell are important to understand, even if you never intend to write in that style.

Re:Ask HN: Resources for catching up on modern JavaScript fo... by sametmax on Tuesday April 10, 2018 @01:18PM (#16803110)
Learning just the js language takes one day if you are an experienced programmer. It's a very small language.
Re:Ask HN: Resources for catching up on modern JavaScript fo... by mzzter on Tuesday April 10, 2018 @01:32PM (#16803224)
How is JavaScript a small language at all? It’s comparable to Java in the number of language features.

Java Reference https://docs.oracle.com/javase/specs/jls/se7/html/index.html

JS Reference https://www.ecma-international.org/publications/files/ECMA-S...

Re:Ask HN: Resources for catching up on modern JavaScript fo... by sametmax on Tuesday April 10, 2018 @01:40PM (#16803302)
It's not even on the same planet.

In JS you have a very small number of types, keywords and a ridiculously small stdlib.

I'm not sure what to make of your comment.

Re:Ask HN: Resources for catching up on modern JavaScript fo... by tomc1985 on Tuesday April 10, 2018 @04:50PM (#16805235)
There is a lot of meta-knowledge buried in using those few features that he is probably referring to. Knowledge of language features is one thing, knowledge of when to use them is another
Re:Ask HN: Resources for catching up on modern JavaScript fo... by sametmax on Wednesday April 11, 2018 @04:07AM (#16809000)
That's true for every language.

The only hard part with JS is the accumulation of bad design decision that means you gotta avoid or hack around part of the language.

The rest is just a basic dynamic language with some async semantics. Nothing crazy.

Re:Ask HN: Resources for catching up on modern JavaScript fo... by chatmasta on Tuesday April 10, 2018 @11:46AM (#16802228)
All good points. Some counters:

- Re: React. I actually disagree with this given that OP is an experienced programmer. The react API is very, very simple to learn but difficult to master. The forced conventions are good for productivity. If you use create-react-app, I don't see any reason to put off learning it until later, but of course you should start with the JS basics before installing react. I'm not sure vue would be better; in fact it might be worse as a first experience, just because there is far less documentation / community / ecosystem around it.

- Re: python backend. That's fine, but if the goal is to learn JS, you're not learning much by writing the backend in Python are you?

Nice tip on the crossbar.io, I'm going to check that out.

Re:Ask HN: Resources for catching up on modern JavaScript fo... by paultopia on Tuesday April 10, 2018 @11:48AM (#16802252)
Disagree slightly with the point about far less documentation/community/ecosystem on Vue. The Vue documentation is stunningly amazing---probably the best out-of-the-box documentation I've ever seen for a library, and that really makes it vastly easier to learn than its competitors.
Re:Ask HN: Resources for catching up on modern JavaScript fo... by sametmax on Tuesday April 10, 2018 @12:00PM (#16802350)
> Re: python backend. That's fine, but if the goal is to learn JS, you're not learning much by writing the backend in Python are you?

It's true that backend JS has the most modern dialect, and without any need for a transpiler. And OP did mention "modern".

Re:Ask HN: Resources for catching up on modern JavaScript fo... by sireat on Tuesday April 10, 2018 @04:53PM (#16805262)
If you want modern Javascript I'd say React is a better choice than Vue.

I spent 10 years doing embedded Javascript(not web) and wanted to see what modern webdev was like.

Vue came highly recommended but I do not feel like I am writing pure Javascript when writing Vue. Vue might be a better choice for someone who does not want to write JS.

The hip people told me to avoid React (FB, too massive etc).

Surprisingly React feels great for writing Javascript. Just learn ES6 features(arrow functions for one) and go to town.

Re:Ask HN: Resources for catching up on modern JavaScript fo... by hannofcart on Tuesday April 10, 2018 @11:57AM (#16802318)
In my opinion, prototypal inheritance does not belong in the same league of importance as closures, async programming, promises in the "modern JavaScript" ecosystem. In fact, I'd replace it with generators.
Re:Ask HN: Resources for catching up on modern JavaScript fo... by adamsea on Tuesday April 10, 2018 @11:41AM (#16802174)
Agree with all of the above. ES6 is great, as is (imho) using Javascript in a functional-programming style.

And, 100% avoid the "class" keyword.

When I was learning node.js I used "learnyounode", a terminal-based game/learning program. It was great. It had lessons which appropriately increased in difficulty, code examples, and guidance on which documentation to peruse in order to complete the coding assignments (each of which was a tiny application). There's one for Javascript too. They are both here:

https://github.com/workshopper

Learning to understand closures and the "this" context (including prototypical inheritance) can take a bit, but is extremely useful and important.

Related to the above, learn the Javascript "module pattern" design pattern.

When you get to the appropriate point, the source code of Redux is fairly simple and clearly written: https://github.com/reactjs/redux/tree/master/src

"Secrets of the Javascript Ninja" is an older book but a good one. So is "Javascript: The Good Parts."

Re:Ask HN: Resources for catching up on modern JavaScript fo... by chrismeller on Tuesday April 10, 2018 @12:54PM (#16802870)
Why would you ever recommend against using actual ES6 classes? Not only is it the new standard, he’s coming from Java...

TBH, the only reason that seems to make sense is some kind of weird “I knew JavaScript before it had classes!” kind of sentiment that wouldn’t actually teach him anything of value.

Re:Ask HN: Resources for catching up on modern JavaScript fo... by chatmasta on Tuesday April 10, 2018 @01:15PM (#16803059)
I use ES6 classes every day, and I would recommend it. However, for someone coming from a language like Python, it's easy to get confused over inheritance issues where JS does not behave like Python (or Java for that matter).

It doesn't need to be extreme. I just recommended writing one or two "classes" using the old style, in the beginning, because that's a great way to solidify understanding of how the inheritance actually works. Whereas when you're using ES6 classes, you're using hidden abstractions that can make debugging very confusing if you don't know what the "class" keyword is doing.

Re:Ask HN: Resources for catching up on modern JavaScript fo... by MoTTs_ on Thursday April 12, 2018 @02:52AM (#16818578)
On the contrary, classes and inheritance in both Python and JavaScript behave basically the same. In Python, classes are objects (a building, not a blueprint), and inheritance is done by delegation.

https://i.imgur.com/p9Kw815.png

If you've used Python classes and inheritance all this time and never felt confused, then people can also use JavaScript's classes and inheritance and never feel confused.

Re:Ask HN: Resources for catching up on modern JavaScript fo... by chrismeller on Tuesday April 10, 2018 @03:02PM (#16804104)
I came from a C# background, not Java, but didn’t find anything supremely confusing about class inheritance in JS. Differences to be sure, but nothing that was groundbreaking.

Debugging I can see as being a reasonable argument - as you step through code you should understand what “proto” means. That’s the most compelling reason I’ve seen thus far...

Re:Ask HN: Resources for catching up on modern JavaScript fo... by thinkxl on Tuesday April 10, 2018 @01:05PM (#16802952)
Prototypal inheritance plays a huge role in understanding the language because JavaScript uses it for everything.

It might be a good idea to learn about this before using ES6 classes; remember that ES6 classes are syntactic sugar on top of prototypal inheritance anyway. They wouldn't learn legacy patterns, but the actual pattern that JavaScript uses.

Re:Ask HN: Resources for catching up on modern JavaScript fo... by chrismeller on Tuesday April 10, 2018 @03:11PM (#16804193)
I grant you that it plays (or at least played) a huge part, but as things move towards ES6 classes (which are very similar to every other language with classes), I would still argue that you’re insisting upon learning prototype inheritance for no real reason.
Re:Ask HN: Resources for catching up on modern JavaScript fo... by thinkxl on Tuesday April 10, 2018 @05:50PM (#16805845)
You are missing the point; if you use JavaScript, you use prototypal inheritance whether you like it or not, e.g.:

  function getUser() {} 
That is creating an instance of the `Function` constructor object[1][2]. In a Classical (as classes) language, you would see that like this:

  // `Function` being a class 
  function getUser extends Function {}
but because JavaScript is purely prototypal, this works differently.

You say that there's no reason to learn prototypal inheritance, well, the only and valid reason is that to write at least decent JavaScript you have to understand how it works behind the scenes.

* [1] - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe...

* [2] - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe...

Edit: add links

Re:Ask HN: Resources for catching up on modern JavaScript fo... by tytytytytytytyt on Tuesday April 10, 2018 @01:16PM (#16803082)
> The "class" keyword is just syntactical sugar on prototypical inheritance so it's a good idea to learn the raw form before the sugared form.

Idk how he could be more clear about why.

Re:Ask HN: Resources for catching up on modern JavaScript fo... by alibarber on Tuesday April 10, 2018 @11:08AM (#16801888)
Thanks - those types of tips were exactly what I was looking for. I've had an idea for a webapp brewing on the side but wasn't sure how best to jump in, and also the main things to look out for when learning something new.
Re:Ask HN: Resources for catching up on modern JavaScript fo... by btilly on Tuesday April 10, 2018 @01:31PM (#16803220)
Async programming / closures. You can't just call a function on an object in a loop like you can in Python.

Actually if you're willing to use https://github.com/scopsy/await-to-js as a transpiler, and await/async on the back end in node, then you actually CAN just call a function in a loop like you would in Python, modulo a tiny amount of decoration that is pretty similar to how you'd do it with Twisted.

Re:Ask HN: Resources for catching up on modern JavaScript fo... by reacweb on Tuesday April 10, 2018 @11:28AM (#16802058)
Do you think he should use typescript or javascript? Would typescript slow down learning or help learning?
Re:Ask HN: Resources for catching up on modern JavaScript fo... by drinchev on Tuesday April 10, 2018 @11:31AM (#16802080)
Definitely it will slow down learning, but most of all you will be quite confused in the end, what is JavaScript and what is TypeScript.
Re:Ask HN: Resources for catching up on modern JavaScript fo... by rhacker on Tuesday April 10, 2018 @11:36AM (#16802125)
If he's coming from typed languages he should definitely learn Typescript or at LEAST Javascript with Flow.
Re:Ask HN: Resources for catching up on modern JavaScript fo... by chatmasta on Tuesday April 10, 2018 @01:35PM (#16803261)
I wouldn’t touch TS until I had an understanding of JS. The many libraries without typings will just make things confusing IMO.
Re:Ask HN: Resources for catching up on modern JavaScript fo... by EastLondonCoder on Tuesday April 10, 2018 @11:40AM (#16802160)
Brilliant recommendations. I would like to add learning redux as soon as possible is a good thing.
Re:Ask HN: Resources for catching up on modern JavaScript fo... by adamsea on Tuesday April 10, 2018 @11:43AM (#16802199)
I would say yes and no. Closures, prototypical inheritance, etc, i.e. the language basics are all are really helpful to understand and be comfortable before using redux. Also, if the OP isn't using React.js then Redux may not be appropriate.

That said, yeah, if you are using React.js you should definitely learn and use redux.

Re:Ask HN: Resources for catching up on modern JavaScript fo... by acemarke on Tuesday April 10, 2018 @12:52PM (#16802848)
I'm a Redux maintainer. We generally recommend learning React first before trying to learn Redux, if only to minimize the number of new concepts you're dealing with at once. And yes, the more comfortable you are with actually using JS, the better you'll be at both React and Redux.

It's worth noting that Redux is not tied to React, and can be used with any UI layer (Angular, Ember, Vue, vanilla JS, etc).

Re:Ask HN: Resources for catching up on modern JavaScript fo... by lhlmgr on Tuesday April 10, 2018 @11:19AM (#16801974)
thanks for that! it was an instant-star.

However, my approach was to start with an more-or-less small project with react / redux / typescript. In the beginning it was a pain, but now it works.. mostly.