6 ms·

Why would flow + es6 be better?

by Nemcue 10y ago

MehdiHK 10y ago
Avoid vendor locking. Someday in near future if you don't like flow anymore, you can just strip all type annotations with Babel and move on. You are not risking ending up like coffeescript.
- treehau5 10y ago
  Also, you can progressively opt in to add typing information, while still getting most of the benefits without.
  - whatever_dude 10y ago
    The same can be done with TypeScript. Type inference has been added to it in 2015.
    - treehau5 10y ago
      Awesome, did not know this.
    - shados 10y ago
      TypeScript type inference is minimal though and doesn't go very far. It falls back to "any" very quickly (and if you use the noImplicitAny option, then you have to type almost everything). It does a decent enough job at return types, but not a whole lot beyond that.
      - whatever_dude 10y ago
        Do you have a use case where something would be correctly inferred in Flow but not in TS?
        dsp1234 10y ago
        The classic example is: function double(x) { return x * 2; } const result = double("foo"); Which passes in TS, but fails in Flow. In TS, the 'x' parameter to the double function is inferred as Any.
- dangoor 10y ago
  TypeScript compiles to JS in a straightforward manner as well. If you wanted to move away from TS, you could simply have the TS compiler compile to ES6 and you're done.
  - MehdiHK 10y ago
    But that'd still be transpiled code, right? After getting rid of flow it will be exactly same minus the type annotations. Same cannot be said about typescript considering various language features and syntactic sugar TS offers. Will it run? Yes. Will it feel that it was written by me? That depends.
    - eknkc 10y ago
      With target esnext, it produces almost the same output with some spacing differences. Sans the annotations obviously.
    - Rapzid 10y ago
      Your equivalence with transpiling coffeescript is false. TS doesn't really have "syntactic sugars". Just about everything in it(less the types of course) is pretty far along in the ES adoption process. There are a couple exceptions like decorators that are called out in a very visible manner. If you target ES6 your code may look identical. Even much of the ES5 down leveling produced code that looks like a person wrote it. I converted a 10k line coffeescript project(with async/await !) to JS and then TypeScript. The similarities are so far apart they might as well be in different dimensions. But, if you don't want to take a rando posters word for it, it's pretty easy to make a little sample project and see if the output is to your liking.
    - whatever_dude 10y ago
      > Same cannot be said about typescript considering various language features and syntactic sugar TS offers I think you're vastly misinterpreting what TS is. It's not anything like CoffeeScript. It's JS plus types and a few other features like Interfaces or advanced ECMAScript features when targetting older versions of the standard. If you strip away types by exporting to your ECMAScript target of choice, you'll get real JavaScript with the same style as it was written in TypeScript. It's exactly the same thing you'd get with Flow in that sense. The only additional code you'd get would be for polyfills, but a) those are minimal and b) those will only appear if you export to an older ECMAScript version than the one you wrote it in. There is no vendor lock.
- whatever_dude 10y ago
  That's an objectively incorrect assertion if you're applying that to TypeScript. The same can be done to it that would be done to Flow: you can just either strip types manually, or just do a single export to your ECMAScripttarget of choice. It'll be native JavaScript. Even the little shims/polyfills it does (to support older ECMAScript versions if you wish to export to it) are optional and can be disabled.
  - mohamedhegazy 10y ago
    TypeScript has `--target ESNext` this will strip out any TypeScript-specific type annotations, and leave you with standard-track-only JS code that looks identical to your input (modulo type annotations).
- icholy 10y ago
  > Avoid vendor locking. It's open source. > you can just strip all type annotations with Babel and move on. Are you implying that this isn't possible with TypeScript?
- dsp1234 10y ago
  If you're afraid of vendor lock-in, but fine with comments then you can just put all of your typing information in jsdoc comments. https://github.com/Microsoft/TypeScript/wiki/JSDoc-support-in-JavaScript https://github.com/Microsoft/TypeScript/wiki/JSDoc-support-i...
- hzoo 10y ago
  FYI we do have an issue open about TS https://github.com/babel/babylon/issues/320 https://github.com/babel/babylon/issues/320 so that we could eventually support TS in Babel as a plugin and then create the same strip-types-plugin just like Flow.
davesnothere 10y ago
One reason flow might be considered "better" (context is key) is that it plays well with the babel ecosystem, letting one pick and choose their language features.
- WorldMaker 10y ago
  Typescript and Babel play well together, too.
  - Rapzid 10y ago
    Yeah, I personally don't mess around with Babel but I imagine you could just take TypeScript's ES6 output and feed it through babel in your gulp/webpack pipeline.
    - vivainio 10y ago
      Some people were doing that before TS got async/await compilation directly to ES5 (in TS 2.1). Right now, having Babel in the TS pipeline is not that useful anymore.
      - johnny_reilly 10y ago
        It's very useful if you want to use native APIs that arrived with es6: Promise, Map etc. TypeScript doesn't shim those
      - mercer 10y ago
        I've had some major headaches getting TypeScript to work with Babel and Webpack 2. The main reason I had to use Babel was because I wanted to use Webpack 2's tree shaking feature. Do you know if it's possible to use just TypeScript and Webpack without Babel, and still take advantage of tree shaking? Honestly this is the main thing keeping me from using TypeScript. I've spent hours, maybe days trying to deal with the mess of Babel/webpack/TS combined with ES6 modules (necessary for tree shaking). Another problem I ran into was using various packages that weren't typed, but I suppose I can solve that by 'allowing' implicitAny. I'd really love some advice on this because I want to use TypeScript. It's just been a major headache so far because things are complicated enough with all the other moving parts (Babel presets, import vs require, better but still not well documented Webpack 2, etc.).
treehau5 10y ago
- You are writing javascript, not typescript. - When typescript came out, I was an early adopter, and a lot of it's touted benefits were the class-like syntax and constructors to make it more palatable to enterprise shops (not for me, but it was easier to sell to higher ups), this is mostly a moot point now. - flow can be attached to any codebase as the codebase stands easily. It is, I have found, difficult to bring TS into an existing project. - flow fits nicely into existing popular js tooling, mainly babel and react. - no risk of vendor lock in. Maybe TS compiles to pure 100% syntactically correct javascript today, maybe it doesn't in the future. It isn't javascript, so I won't know.
- whatever_dude 10y ago
  At the risk of probably repeating myself, allow me to give my $0.02: > - You are writing javascript, not typescript. Flow's and TypeScript's distance to JS world are the same, and are very similar in most cases. If you want to add type to one, it's the same as in the other. The only difference here is the file extension, since TS tends to like .ts/.tsx. > - When typescript came out, I was an early adopter, and a lot of it's touted benefits were the class-like syntax and constructors to make it more palatable to enterprise shops (not for me, but it was easier to sell to higher ups), this is mostly a moot point now. True, although IMO the greatest feature of TS is making your code stronger, not compiling things that are already part of some ECMAScript version. >- flow can be attached to any codebase as the codebase stands easily. It is, I have found, difficult to bring TS into an existing project. True, with TS it's more of a lateral move rather than drops here and there. >- flow fits nicely into existing popular js tooling, mainly babel and react. TS works just as well; better, IMO, because dev tools (editors, linters) have better TS support in my experience. Writing React in JS to me makes me feel like I'm using Notepad since there's so much TS helps me with that is lost when using a purely dynamic language. >- no risk of vendor lock in. Maybe TS compiles to pure 100% syntactically correct javascript today, maybe it doesn't in the future. It isn't javascript, so I won't know. It does compile to pure JS so ejecting TS is easy; it's trying to follow future standards and proposed changes, not create something different; the project is open source. There is no vendor lock in.
  - 10y ago

Why would flow + es6 be better?

by Nemcue 10y ago

Why would flow + es6 be better?

Avoid vendor locking. Someday in near future if you don't like flow anymore, you can just strip all type annotations with Babel and move on. You are not risking ending up like coffeescript.

treehau5 10y ago
Also, you can progressively opt in to add typing information, while still getting most of the benefits without.
- whatever_dude 10y ago
  The same can be done with TypeScript. Type inference has been added to it in 2015.
  - treehau5 10y ago
    Awesome, did not know this.
  - shados 10y ago
    TypeScript type inference is minimal though and doesn't go very far. It falls back to "any" very quickly (and if you use the noImplicitAny option, then you have to type almost everything). It does a decent enough job at return types, but not a whole lot beyond that.
    - whatever_dude 10y ago
      Do you have a use case where something would be correctly inferred in Flow but not in TS?
      - dsp1234 10y ago
        The classic example is: function double(x) { return x * 2; } const result = double("foo"); Which passes in TS, but fails in Flow. In TS, the 'x' parameter to the double function is inferred as Any.
dangoor 10y ago
TypeScript compiles to JS in a straightforward manner as well. If you wanted to move away from TS, you could simply have the TS compiler compile to ES6 and you're done.
- MehdiHK 10y ago
  But that'd still be transpiled code, right? After getting rid of flow it will be exactly same minus the type annotations. Same cannot be said about typescript considering various language features and syntactic sugar TS offers. Will it run? Yes. Will it feel that it was written by me? That depends.
  - eknkc 10y ago
    With target esnext, it produces almost the same output with some spacing differences. Sans the annotations obviously.
  - Rapzid 10y ago
    Your equivalence with transpiling coffeescript is false. TS doesn't really have "syntactic sugars". Just about everything in it(less the types of course) is pretty far along in the ES adoption process. There are a couple exceptions like decorators that are called out in a very visible manner. If you target ES6 your code may look identical. Even much of the ES5 down leveling produced code that looks like a person wrote it. I converted a 10k line coffeescript project(with async/await !) to JS and then TypeScript. The similarities are so far apart they might as well be in different dimensions. But, if you don't want to take a rando posters word for it, it's pretty easy to make a little sample project and see if the output is to your liking.
  - whatever_dude 10y ago
    > Same cannot be said about typescript considering various language features and syntactic sugar TS offers I think you're vastly misinterpreting what TS is. It's not anything like CoffeeScript. It's JS plus types and a few other features like Interfaces or advanced ECMAScript features when targetting older versions of the standard. If you strip away types by exporting to your ECMAScript target of choice, you'll get real JavaScript with the same style as it was written in TypeScript. It's exactly the same thing you'd get with Flow in that sense. The only additional code you'd get would be for polyfills, but a) those are minimal and b) those will only appear if you export to an older ECMAScript version than the one you wrote it in. There is no vendor lock.
whatever_dude 10y ago
That's an objectively incorrect assertion if you're applying that to TypeScript. The same can be done to it that would be done to Flow: you can just either strip types manually, or just do a single export to your ECMAScripttarget of choice. It'll be native JavaScript. Even the little shims/polyfills it does (to support older ECMAScript versions if you wish to export to it) are optional and can be disabled.
- mohamedhegazy 10y ago
  TypeScript has `--target ESNext` this will strip out any TypeScript-specific type annotations, and leave you with standard-track-only JS code that looks identical to your input (modulo type annotations).
icholy 10y ago
> Avoid vendor locking. It's open source. > you can just strip all type annotations with Babel and move on. Are you implying that this isn't possible with TypeScript?
dsp1234 10y ago
If you're afraid of vendor lock-in, but fine with comments then you can just put all of your typing information in jsdoc comments. https://github.com/Microsoft/TypeScript/wiki/JSDoc-support-in-JavaScript https://github.com/Microsoft/TypeScript/wiki/JSDoc-support-i...
hzoo 10y ago
FYI we do have an issue open about TS https://github.com/babel/babylon/issues/320 https://github.com/babel/babylon/issues/320 so that we could eventually support TS in Babel as a plugin and then create the same strip-types-plugin just like Flow.

davesnothere 10y ago

One reason flow might be considered "better" (context is key) is that it plays well with the babel ecosystem, letting one pick and choose their language features.

WorldMaker 10y ago
Typescript and Babel play well together, too.
- Rapzid 10y ago
  Yeah, I personally don't mess around with Babel but I imagine you could just take TypeScript's ES6 output and feed it through babel in your gulp/webpack pipeline.
  - vivainio 10y ago
    Some people were doing that before TS got async/await compilation directly to ES5 (in TS 2.1). Right now, having Babel in the TS pipeline is not that useful anymore.
    - johnny_reilly 10y ago
      It's very useful if you want to use native APIs that arrived with es6: Promise, Map etc. TypeScript doesn't shim those
    - mercer 10y ago
      I've had some major headaches getting TypeScript to work with Babel and Webpack 2. The main reason I had to use Babel was because I wanted to use Webpack 2's tree shaking feature. Do you know if it's possible to use just TypeScript and Webpack without Babel, and still take advantage of tree shaking? Honestly this is the main thing keeping me from using TypeScript. I've spent hours, maybe days trying to deal with the mess of Babel/webpack/TS combined with ES6 modules (necessary for tree shaking). Another problem I ran into was using various packages that weren't typed, but I suppose I can solve that by 'allowing' implicitAny. I'd really love some advice on this because I want to use TypeScript. It's just been a major headache so far because things are complicated enough with all the other moving parts (Babel presets, import vs require, better but still not well documented Webpack 2, etc.).

treehau5 10y ago

- You are writing javascript, not typescript. - When typescript came out, I was an early adopter, and a lot of it's touted benefits were the class-like syntax and constructors to make it more palatable to enterprise shops (not for me, but it was easier to sell to higher ups), this is mostly a moot point now. - flow can be attached to any codebase as the codebase stands easily. It is, I have found, difficult to bring TS into an existing project. - flow fits nicely into existing popular js tooling, mainly babel and react. - no risk of vendor lock in. Maybe TS compiles to pure 100% syntactically correct javascript today, maybe it doesn't in the future. It isn't javascript, so I won't know.

whatever_dude 10y ago
At the risk of probably repeating myself, allow me to give my $0.02: > - You are writing javascript, not typescript. Flow's and TypeScript's distance to JS world are the same, and are very similar in most cases. If you want to add type to one, it's the same as in the other. The only difference here is the file extension, since TS tends to like .ts/.tsx. > - When typescript came out, I was an early adopter, and a lot of it's touted benefits were the class-like syntax and constructors to make it more palatable to enterprise shops (not for me, but it was easier to sell to higher ups), this is mostly a moot point now. True, although IMO the greatest feature of TS is making your code stronger, not compiling things that are already part of some ECMAScript version. >- flow can be attached to any codebase as the codebase stands easily. It is, I have found, difficult to bring TS into an existing project. True, with TS it's more of a lateral move rather than drops here and there. >- flow fits nicely into existing popular js tooling, mainly babel and react. TS works just as well; better, IMO, because dev tools (editors, linters) have better TS support in my experience. Writing React in JS to me makes me feel like I'm using Notepad since there's so much TS helps me with that is lost when using a purely dynamic language. >- no risk of vendor lock in. Maybe TS compiles to pure 100% syntactically correct javascript today, maybe it doesn't in the future. It isn't javascript, so I won't know. It does compile to pure JS so ejecting TS is easy; it's trying to follow future standards and proposed changes, not create something different; the project is open source. There is no vendor lock in.
- 10y ago