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Sell Me On Typescript

James 'Dante' Midzi on May 28, 2022

I'm a Python developer and this strictly typed langauges this something I left after I finished my Diploma (C, C++, Java) I later got into React a...
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tqbit profile image
tq-bit • Edited

"why must I use it?"

You don't have to, but I think you'll learn a lot if you do.
^this

All I can do is to promise you'll thank every developer (including your past self) if they write their code with static types.

Don't like TS for typing? Maybe you'll prefer JSDoc: typescriptlang.org/docs/handbook/j...

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psypher1 profile image
James 'Dante' Midzi

Granted, I could have chosen better wording. Most of the times I come across people hyping TS it's usually "it'll make you faster". The way I work, fast is not a metric I focus on. But using that, I have spent more time doing something in typescript than I would have if It were just JavaScript.

It's not that I don't like it, I'm just not convinced more than anything. JSDoc you say, I'll have a look at it .

Thank you

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peerreynders profile image
peerreynders

I like the idea of JS Doc TS but in my judgement you have to be good with TypeScript first before trying to tackle JS Doc TS (and it has an even larger hurdle for initial setup). The best JS Doc TS example I know of is Preact.

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psypher1 profile image
James 'Dante' Midzi

Oh boy....

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tqbit profile image
tq-bit

Most of the times I come across people hyping TS it's usually "it'll make you faster"

The thing here is - it does make you faster on 'common' development projects. This implies, you:

  • work in a team
  • have a dev workflow including code review, exhaustive testing, and so forth
  • re-write a bunch of features in each sprint phase

I think not being convinced is okay. My portfolio is written in JS as well. And I see no good reason to rewrite it just for the sake of adding Typescript to the codebase. The last two hackathons on dev.to, I wrote using Typescript. I didn't work on them regularly. Since they use several layers of abstraction, VSCode's TS intellisense was really helpful to understand

  • function / method argument types
  • return value types
  • how to instantiate a class
  • getters from Pinia

That's what I meant about the "you'll thank every developer later" part. The less mental capacity you use memorising what you built earlier, the easier it is to plan what to write next. Or whether you can re-use or refactor your modules.

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James 'Dante' Midzi

This makes sense. When I do work on a project that uses it, then I'll dedicate more time to. As of now, I don't have a valid reason...

The whole affair drove me to build the portfolio with Eleventy instead - to actually see what javascript is necessary for it. For that, I'm grateful

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peerreynders profile image
peerreynders • Edited

Last time I checked there were additional hurdles to using TypeScript with 11ty.

Enough for me to consider using Astro instead if TypeScript was a critical consideration.

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James 'Dante' Midzi

Oh no, Eleventy was after... I was initially building in Next.js with TS..

Then the TS thing made me decide to forgo frameworks altogether

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Sir Broddock

My recommendation would be to not let it slow you down. Make good use of the typescript config file, ensuring that the strictness is calibrated to the level you need. It's phenomenally productive to catch sneaky bugs at compile time, even if it may not seem that way on the front leg of dev.

The awesome thing about the ts-config compiler options is that you can scale them up over time. The goal is to have full strictness enforced, but if and when that slows you down then by all means dial it back. The goal is DX and developer productivity, it just so happens that specifying types at compile time do allow for huge amounts of preventative measures

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James 'Dante' Midzi

See, no one ever mentioned this to me - that I can choose how I want to work.

I will look into making it work for me and not the other way around.

This makes more sense

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peerreynders profile image
peerreynders • Edited

I'm not particularly fond of TypeScript - overall I view it as having poor ROI but decided to learn it anyway so that I could at least have a somewhat coherent base to criticize it from.

That said I accidentally fell into an interesting work flow. I was trying to use uvu with TypeScript. It uses tsm to test TypeScript code.

With that setup you can actually focus entirely on getting your unit tests done first without paying any attention to TypeScript - type checking (linting) only occasionally when the test results don't make any sense (i.e. overall the tests where more effective pointing out issues than TypeScript).

Once you're done with a unit of work you can then focus on what TypeScript is complaining about - "oh yeah, I better clean that up".

That allows a "JavaScript style" work flow with (a sprinkling of) explicit TypeScript types for documentation.

Basically use fast non-checking transpilation with a fast loader for reqular work and only run the full type check at the end or when things get weird.

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James 'Dante' Midzi

This is realty interesting... Is there a public repo I can look at?

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peerreynders profile image
peerreynders • Edited

Not sure what you are hoping to find but recently I put together solid-hackernews-a.

Vite uses esbuild for "discarding type annotations" - so npm run dev doesn't type check (presumably that is supposed to happen a priori in the IDE/language server enabled editor). npm run lint:types is used separately for static type checking.

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James 'Dante' Midzi

Not looking to find anything specific. I understand technologies better by having a look at how people use them over reading the docs...

I'll have a look, thank you

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grantdotdev profile image
Grant Riordan

Once you get the "hang of it" you won't be battling with it. It will become second nature to build variables and type them.

By doing so you won't see as many type errors and such. It's just a learning curve. Persevere and you will seen the benefits !

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James 'Dante' Midzi

I'll keep at it, without a doubt... I wanted to hear what other people say about it

Thank you

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mistval profile image
Randall

TypeScript has a fairly large learning curve (I would say larger than some real statically typed languages like C# and Java) and it WILL slow you down on small projects. It's also easy to use TypeScript poorly, and not get much benefit out of it, if you just throw any at any sign of a problem.

But when you get into large projects, especially when you're working with other people, it will accelerate you and make your code better (if you use it well, anyway). Refactoring gets much easier, intellisense gets much better, you know what kind of data you're working with.

Some people are all-in on TypeScript and use it for everything. I'm not one of them - I find it a waste of time for relatively small, personal projects. But I'd never consider using plain JavaScript for anything substantial anymore.

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James 'Dante' Midzi

Oh yes the any thing was the first thing I took to heart when i watched Jack Herrington's series. To that effect, i understand not to throw any everywhere

This is understandable, thank you for the explanation

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Justin Henry

My argument for typescript has 2 parts:

  • intellisense benefits from the definitions as you write them, and it paints a picture for other developers that come before you (though I know jsdoc can do this as well, it is easier for developers used to strictly typed languages to adapt)
  • many of the features of typescript come out long before javascript adopts them, so it has a great track record of predicting what javascript will do. Having a head start on newer patterns gives you an advantage when the world eventually phases out typescript and leaning into most of its features.

My own personal reasons for using typescript involve being able to be self-accountable and make sure all the contracts I write with the code are properly handled. It can give you some freedom when writing internal code, so you don't need to necessarily write tons of runtime checks on the data since you know the compiler will check for a lot of that. The only areas where data checking is really important in typescript is when you have an external data source (or input) that could come in during runtime that can possibly not meet the structure contract. As you adapt to the nuances of the flavored language, it gets easier and faster to build.

The biggest evidence of your struggle not being with the language is that the code you write does not obey the rules you write, so its more of an issue of how you are writing the code, not with typescript itself. Think of it like training wheels. Eventually with enough coding in typescript, writing a specific way will become second nature and you can take those practices with you into JavaScript.

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James 'Dante' Midzi

Contacts? Web3?

I'm not foreign to typed languages, Typescript has just given me more grief than the other ones.

I wanted to understand the increasing adoption of it

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jwhenry3 profile image
Justin Henry

For many, the fact that javascript isn't typed keeps people from working on web projects, and typescript was a way to bridge that gap. Being that it was developed by Microsoft, perhaps it was developed to bridge the gap between C# and web so they could reuse developers from backend on frontend to a degree, for familiarity.

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eshimischi profile image
eshimischi • Edited

Typescript is simply the same Javascript but extended with typing, but not only that. You’ll become better JS dev, with the full picture of this technology whether you use it widely or not, OOP, style of coding, tests, security, new features (ES2022..) and etc.

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curiousdev profile image
CuriousDev

You do not "have to" use it. You would use it, because from what it offers on top of JavaScript you could think it is worth it. There is no need to use it, because you "have to". Typescript bascially is just an extension of JavaScript and allows you to use strict typing, which would make it comparable to lanuages like C#. Editors can make use of it and make development easier (show you allowed methods etc.) as well as allow you to integrate these types as a kind of "rules", which will lead to code, which does not get built, if you break these "rules". There would be no error during the execution in this specific cases, if you could not use it this way. If you want to use some of these points, which I just have described, for your project, you can see them as a must.
But you are not forced to used it and if you are still learning JavaScript, then stick to it for some time before you add with TypeScript to the language's complexity (my opinion at the moment).

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James 'Dante' Midzi

Yeah, I'm noticing my wording could have been better (writing while tired)

My question was more on the "why" I see a number people advocating the switch to it. My question comes as my JS is solid enough to do what I need, so why would consider adding TS to the mix is all

Thank you for the elaboraion.

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curiousdev profile image
CuriousDev

But I am also sorry, if my answer has been too serious. Thanks for your kind response.

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psypher1 profile image
James 'Dante' Midzi

It's alright... I got your thoughts as well as valuable information - which was my intention.

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matthewbdaly profile image
Matthew Daly

Adding types to your code in general is tremendously helpful when working on larger projects, regardless of the language. I've found static analysis tools like Psalm incredibly useful in PHP as well - it's found an awful lot of problems in legacy code.

There's a few options for adding types to JavaScript and while I have used Flow in the past, and still prefer it conceptually to the idea of a whole new language, the tool support is significantly better in Typescript. There are some things Flow does better (opaque types are frustratingly still not a thing in Typescript), but overall Typescript is the better experience.

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jwp profile image
John Peters

I hear you Brother. I've been told right here on Dev.to that I'm dumb, stupid, illogical, and many other pejoratives. They all were Javascript only purists who even denounced their own language adopting classes. These are the same folks that write 5,000 line mono repos filled with magic strings who don't follow DRY. Talking about insanity.

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brense profile image
Rense Bakker

You should only use typescript if you care about the mental wellbeing of whoever has to maintain the code after you're done with it.

Btw, you can always make typescript happy by typecasting to unknown firsts and then any. Not saying you should do this in production code, because you essentially lose all the benefits of typescript if you do this, but it can be helpful while learning. Once you get your code running, you can revisit the ugly type castings and determine how much time you want to take to "fix" it (spoiler: its usually much easier than you think and gets even easier as you learn more about the typescript typing system).

It also helps to use packages that have proper typings, or that have associated @types packages. You don't usually have to do any typing when packages are properly typed.

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brense profile image
Rense Bakker

Oh and another thing people usually run into:

type SomeType = {
  foo: 'bar'
}

function helloWorld(param: string) {
  const myObj: SomeType = {
    foo: param // Type 'string' is not assignable to type '"bar"'
  }
}

function helloWorld2(param: string) {
  const myObj: SomeType = {
    foo: param as 'bar' // You have to use string literal "bar"
    // You can either type cast, or change the type of param from string to 'bar'
  }
}
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Joe Mainwaring • Edited

The primary value-add that I have found with TypeScript is that its features add quality controls to your JavaScript project.

Is it necessary? No, but the value does become evident when an active project scales in complexity and age.

One of my active SaaS products is a Node.js app that started in 2012. Little/no tests, callback hell, and enough features to sell to the enterprise. When I was the team lead on that product’s mobile application, I would have to remediate bugs several times a year when a team member building features for the web modified a shared method and removed/modified an output. If we had types (or tests tbh) around the method’s I/O contract then it would have been caught before merge.

Additionally, callback hell paired with an architecture that IDE’s didn’t fully understand meant significantly more time mapping out process flows within the application. I had to do it a couple times when turnover left me as the one responsible; those efforts took several hours over multiple days, often repeating the exercise multiple times to validate the flow was accurate.

Today, I write all of my application source in TypeScript for new projects if I’m building a JavaScript runtime, but some things like Grunt.js are still authored as regular JavaScript

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James 'Dante' Midzi

Thank you so much for explaining in this much detail. This kind of information is what I was looking for.

This question was shared on Twitter and some of the responses there were discouraging. If i was starting out,I would have given up on it entirely.

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Anuj Singh

for frontend, i don't think it requires that much of types except when you are passing different data throughout the components and for the back end it becomes incredibly useful when you are able to look up what you need to pass and in which format

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Rémy 🤖

Well I don't know.

On one hand I love static typing. In Rust or Kotlin, it takes you by the hand and helps you figure where you are and what you are doing. Very useful.

There is also the case of typing annotations in Python which are super useful for the same reason. I write them all the time and it's no bother at all.

But then when I try TypeScript I feel like I'm fighting against the world. The whole JS world is not built around typing and especially inputs from the API. Taking in all this external data (which let's face it is the largest chance of getting a typing problem) is always super tricky.

On the other hand I'm using Vue and PyCharm, which handles Vue super well so all the auto-complete basically just works without me having to take care of annotating anything.

Not sure what to make of that. JSDoc is indeed probably a better way to go. Getting 99% compliance (JSDoc) is easy but 100% compliance (TS) can be a fucking pain in the ass.

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Charlie J Smotherman

Just another layer of crap that's not needed in most project's.

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deltd3v

Have you tried typescript yet ?
What was your experience like ?
After trying out typescript by building some toy project, why on earth would you go back to using some awful alternative like flow or even @JSDoc

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James 'Dante' Midzi

Yes, I ask because I have tried it and what I am looking for is more information

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wjk22 profile image
Wojtek Kalka

Hey learn brainf***, teaches you something .. there is nothing you have to, but code is just a lot nicer to read and you can avoid some bugs easy ..

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Ikfreecharles

A big advantage of TS is the way it helps you check logic errors you won't catch using only Js. A lot of times, I don't even bother writing tests for these, cause well, TS done most of the checking for me indirectly. Working in a team, TS helps to prevent a lot of programming error types also. Even if these are the only two merits, it's totally worth it for me.

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Luca • Edited

Maybe a little dated, but I've found this article really insightful:

medium.com/javascript-scene/the-ty...

 
psypher1 profile image
James 'Dante' Midzi

This I understand, I had specifc questions in reagrds to Typescript is all

 
psypher1 profile image
James 'Dante' Midzi

To make sure we wouldn't catch up to them 😂😂😂

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Renan Ferro

In a nutshell, TypeScript is a strongly typed programming language that builds on JavaScript and this is so nice!

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jwp profile image
John Peters

Seems like there are two camps 1. The haters and 2. The lovers of TypeScript.

I'm a lover of it for one major reason Intellisense. Ok two reasons, compile time errors instead of runtime errors.

Runtime errors and lack of intellsense are prehistoric.

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huncyrus

I believe you should not be "sold" on technology. You should choose whichever you would like to use, whichever fulfil better your goals and help to achieve it.
Sometime make sense to work with TS, sometime simple JS is better. Sometime should be plain ansi-c, sometime Java.
The real question: why do you wan't to limit yourself and select between?

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Dániel Sebestyén

IMHO TS itself does nothing else then clears a bit of context of our code.
If you don't know js but came from any other strongly typed language, it helps you to understand what's going on with typeflow - assuming the project is properly typed - and gives you some insights of the surroundings, like it's typed for node or browser env.
But to really make code that is efficient and consumable, discoverable you still have to understand javascript, since it is just a superset of it.

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Jack • Edited

The cost of learning and applying typescript is quite high. It will slow you down at first.
The main early benefit is type safety and intellisense. But it often feels like it's a lot of work for little gain.
But in my experience, you reach a point where you suddenly find yourself moving much faster, having way more confidence, and then you'll join another codebase in javascript and you'll realise how much you lose when you don't use static typing.

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Guilherme Oderdenge

I am a die hard TypeScript fan. But not because of TypeScript; I am a die hard fan of it because of types.

At first, it will definitely slow you down. The equation is simple: if you start writing Rust now, you'd be way less productive than you are with Python, for instance. That's not exclusive to TypeScript. But once things click in you head, you won't look back.

In the long term, I think types give you more critical thinking on how you code. That means less bugs, greater developer experience, hence better productivity. In the end of the day, TypeScript is something you'll only find value once you really feel it flow.

But in general, I think TypeScript's benefits (or really, static types benefits) can be summarized to:

  • Greater Developer Experience,
  • You'll be more confident to scale your app,
  • You'll be more productivity to model your projects all around.

That said, I'd say TypeScript is far from being required for small projects. Your portfolio, for instance - you definitely don't need it and barely will feel its benefits, regardless of how proficient you are. But if you are willing to scale your portfolio's features, then I'd say it's a great call.

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cjsmocjsmo profile image
Charlie J Smotherman

And yet there are thousands of Enterprise grade websites out in the wild that don't use typescript. Use if you want to, don't use it, I really don't care, I personally have no use for it (as of now, that may change). Not enough benefit for the cost, I have bigger fish to fry like Rust and Flutter, which I think are a much better investment of my time, but that's me(others may disagree and that's fine). In the end it's nothing more than a personal choice.

Happy Coding

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Stephanie • Edited

Dont use TypeScript unless you know how to use it. When you do some lessons / courses and can use it fluidly to create apps. Then you know why you use it.

TypeScript is absolutely essential in coding. As you secure the flow in your app. What you gain with TypeScript? Debug time is lowered immensely. As you cannot basically make big errors.

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cjsmocjsmo profile image
Charlie J Smotherman

Websites/Javacript ran just fine well before typescript came along, so the notion of typescript being "absolutely essential in coding" is questionable.

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aktoriukas profile image
Gedi

where do i start...

Making "Typescript happy" is making your code happy & avoiding errors down a line. I can see why that is annoying on a small projects, but when project grows there is no way you gonna avoid errors, and most of them will come from the wrong types, incorrect params and so on... You can avoid all of those ( most of it ) with TS.
Having auto-complete is one of the best feature with TS.

In the end, you don't have to use it. For a small project it may even be noth worth using it. But i thing ones you extensivle use it in one project, there is no going back.

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johnb8005 profile image
John B

I moved to TS about 3 years ago. I never looked back.

The ability to work in a pseudo typesafe environment is an absolute game changer and will make your code more robust and easier to iterate on.

It will also force you to do more "engineering" vs simple dev. Needless to mention that I would write many tests which have now become obsolete.

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Aaron Beall • Edited

My bias: huge TS fan here, since the pre-1.0 days.

My first thought is that there's definitely a learning curve. I would say this is the only real disadvantage to typescript, if you aren't already proficient with it (and the latest versions of typescript are quite sophisticated type systems), even if you're well educated in static type systems generally, it's going to slow you down for sure. You're going to struggle with annoying error messages and compiler problems that you know aren't real runtime problems. It sounds like this is what you've run into. I myself hated the idea of static types in front end code originally for the same reasons. I know it's not much of an argument, but I would just say stick with it and once you're proficient enough you'll wonder how you ever wrote JavaScript at scale on teams without it. That's my story and the story of nearly every typescript naysayer I've ever worked with. Just anecdotal but there ya go, happy coding!

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localpath profile image
Garrick Crouch

Refactoring is a breeze and it'll help catch dumb mistakes that you will see no matter what after bundling so in that sense it can save time or make you a more efficient developer. I personally hate that we rely on transpilers but it's an implementation detail for now. Hopefully we'll get static typing in JS and TS can go away.

The setup is actually easy if you study the TS rules for the compiler, don't take it in all at once, there's so much utility to it. Plus you get to incrementally upgrade your project to TS so it's not an all or nothing.

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Anuj Singh

nice jucie auto complition

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k_penguin_sato profile image
K-Sato

If you are just making small web applicatins or wrting simple scripts, JS is all you need.

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Wojtek Kalka

Great minds discuss ideas; average minds discuss events; small minds discuss people

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ayyash profile image
Ayyash

Simple: catch bugs early on during development. That's it, sold :)