Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

TypeScript is surprisingly ok for compilers

matklad.github.io

Post reply on HN
Print view View original

41–50 of 245 posts

Re: TypeScript is surprisingly ok for compilers

#41

Post by foldr »

harrygeez wrote: post #37
foldr wrote: post #34

Earlier quoted context omitted.

Why would it have to instantiate a new V8 for every file? You can just run 'tsc' in your project dir to compile all Typescript files.

I think people often underestimate how much the TypeScript team does to make TypeScript fast and efficient. They have some of the best people in the field working on the type checker

Indeed. I haven't checked the implementation, but I suspect that "don't spin up a separate process for every file" is an idea that has probably already occurred to them :D

Re: TypeScript is surprisingly ok for compilers

#42

Post by lmm »

xscott wrote: post #32
baq wrote: post #17

Earlier quoted context omitted.

The biggest expressivity pain point in practice for me is try/catch not being an expression, so I can’t do const c = try { … }

What does a try expression like this do? Returns null/undefined on a throw? I suspect you could do something like: const c = attempt(() => ... ); where attempt invokes the lambda, catches any exceptions, and does what you want

> What does a try expression like this do? Returns null/undefined on a throw?

If an exception is caught, the expression evaluates to what the catch block evaluates to. (Similar to having if/else be an expression). Of course if the exception isn't caught then it propagates so the expression doesn't take a value.

Re: TypeScript is surprisingly ok for compilers

#43

Post by crooked-v »

moonchrome wrote: post #12
lmm wrote: post #2

Is that really suprising? Typescript is yet another language that has, kicking and screaming, picked up most of the ML featureset. I'd expect it to be, well, fine; the lack of real pattern matching is a pain, so it's going to be inferior to OCaml, but fine, no different from using C# or Swift or Dart or Kotlin or something of that ilk.

That's some very high level view - in reality even tough those languages are in similar categories the experience would be vastly different : TypeScript - powerful type system but shit underlying stdlib and language (no pattern matching/switch expressions) Dart - worse than TS because the object model is closed - so no dynamic freedom, but the type system and expressions are weaker then the rest. Also 0 meta programm…

> no pattern matching/switch expressions

They're still waiting on the do expression proposal for that (https://github.com/tc39/proposal-do-expressions), which has been in the bikeshedding stage for the past five years.

Re: TypeScript is surprisingly ok for compilers

#44

Post by kaba0 »

zkldi wrote: post #33
thdespou wrote: post #27

Earlier quoted context omitted.

Zig can though: const std = @import("std"); pub fn main() !void { const stdout = std.io.getStdOut().writer(); try stdout.print("Hello, {s}!\n", .{"world"}); }

that's not using `try` as an expression. can you do `let foo = try (plus some handling for diverging in the other case?)`

It can and you in fact either have to mark that you return that error when you use try, or you have to provide a default value in a catch block:

  fn potentiallyErrorReturningFunc() !u64 {
    ...
  }

  const foo = potentiallyErrorReturningFunc() catch { 0 };
One notable difference to most other languages is it being a value only, basically a product type of return value XOR error. These error values get serialized into a number by the compiler that is unique, and on the type system level you deal with sets of these error values. Quite clever in case of a low-level system, in my opinion.

Re: TypeScript is surprisingly ok for compilers

#45

Post by jillesvangurp »

lmm wrote: post #2

Is that really suprising? Typescript is yet another language that has, kicking and screaming, picked up most of the ML featureset. I'd expect it to be, well, fine; the lack of real pattern matching is a pain, so it's going to be inferior to OCaml, but fine, no different from using C# or Swift or Dart or Kotlin or something of that ilk.

I've done a bit of typescript and kotlin-js. It always strikes me how close those two languages are. Yes there are lots of differences but they aren't that different and you can transition from one to the other pretty easily. I have my preferences (kotlin) but I can work with both.

IMHO typescript could just cut loose from its javascript compatibility. Why not compile it to wasm instead of transpiling it to javascript? Kotlin is in the process of adding a wasm compiler and they already have a js transpiler. The same code results in a lot smaller binaries and loads a lot faster in wasm form. Browser Javascript is not a great compilation target. And who cares what the minified crap that loads in the browser looks like? The only reason for backwards compatibility is allowing javascript projects to easily transition to typescript. But that's increasingly less relevant now that a lot of projects start out being typescript from day 1.

Of course, Assembly script is already a thing. But why not make that a bit more official? It wouldn't surprise me to see people doing a lot of web development in languages like that in a few years.

Re: TypeScript is surprisingly ok for compilers

#46

Post by gr__or »

Very much apropos:

Going between Rust and TS it is painfully obvious how much sth like tagged enums are missing, which can also be seen in this post.

I know of this [1] proposal for ADT enums which looks like it has stalled. Anyone know of other efforts?

[1] https://github.com/Jack-Works/proposal-enum/discussions/19

Re: TypeScript is surprisingly ok for compilers

#47

Post by alexvitkov »

harrygeez wrote: post #37
foldr wrote: post #34

Earlier quoted context omitted.

Why would it have to instantiate a new V8 for every file? You can just run 'tsc' in your project dir to compile all Typescript files.

I think people often underestimate how much the TypeScript team does to make TypeScript fast and efficient. They have some of the best people in the field working on the type checker

Yes, because it's one of the slowest compilers in the world, and its job is to compile from JavaScript to JavaScript. There are other languages with complex type systems, where the compilers have to do a lot of other additional work on top of typechecking, and are still way faster than TS.

And TypeScript is always slow, not only when you do abuse its type system and require it to do complex inference - I mostly use it for "this is a number" and "this is a object with the following 4 fields" and it's still by far the slowest component in my builds usually

Re: TypeScript is surprisingly ok for compilers

#48

Post by xvilka »

lmm wrote: post #2

Is that really suprising? Typescript is yet another language that has, kicking and screaming, picked up most of the ML featureset. I'd expect it to be, well, fine; the lack of real pattern matching is a pain, so it's going to be inferior to OCaml, but fine, no different from using C# or Swift or Dart or Kotlin or something of that ilk.

This is why once WebAssembly more polished and more common, languages like JS and TS could become obsolete since proper, more powerful languages will suddenly become a valid choice for Web.

Re: TypeScript is surprisingly ok for compilers

#49

Post by pjmlp »

lmm wrote: post #2

Is that really suprising? Typescript is yet another language that has, kicking and screaming, picked up most of the ML featureset. I'd expect it to be, well, fine; the lack of real pattern matching is a pain, so it's going to be inferior to OCaml, but fine, no different from using C# or Swift or Dart or Kotlin or something of that ilk.

C# and Swift have pattern matching.

Re: TypeScript is surprisingly ok for compilers

#50

Post by orra »

jillesvangurp wrote: post #45
lmm wrote: post #2

Is that really suprising? Typescript is yet another language that has, kicking and screaming, picked up most of the ML featureset. I'd expect it to be, well, fine; the lack of real pattern matching is a pain, so it's going to be inferior to OCaml, but fine, no different from using C# or Swift or Dart or Kotlin or something of that ilk.

I've done a bit of typescript and kotlin-js. It always strikes me how close those two languages are. Yes there are lots of differences but they aren't that different and you can transition from one to the other pretty easily. I have my preferences (kotlin) but I can work with both. IMHO typescript could just cut loose from its javascript compatibility. Why not compile it to wasm instead of transpiling it to javascrip…

I'm afraid that's wishful thinking. JS compatibility is core to the TypeScript ethos, regardless of TypeScript's own popularity.

Besides, enums (?) aside, and ignoring typechecking, compiling TS is really easy right now. Switching to WASM is a high ask.

Post reply on HN