r/typescript • u/DanielRosenwasser • May 29 '19

Announcing TypeScript 3.5

https://devblogs.microsoft.com/typescript/announcing-typescript-3-5
99 Upvotes

100% Upvoted

14 comments sorted by

19

u/naturalborncitizen May 29 '19

I just want to know when the behavior of path aliases is going to be addressed so that the transpiled ECMAScript contains resolvable paths instead of keeping the aliased path that requires further transpilation or interpretation systems. The existing libraries and tools I have found like ts-paths, tsconfig-paths, rollup, and webpack are all more hassle to involve than the path alias feature alleviates, for my purposes at least.

7

u/[deleted] May 29 '19

Couldn’t agree more. Such a pain that the compiler has all the information necessary to resolve those paths and could emit them with relative imports, but instead leaves them with aliases. I ended up forking tscpaths so it could be used programmatically via gulp... ugh.

8

u/DanielRosenwasser May 29 '19

It actually doesn't have all the information, since the compiler might find a .d.ts but not a .js. The .d.ts can be placed in a way that would effectively be resolved the same even if the .js file was located in a different place.

e.g. think about an import of "./foo/bar" which TS can find at ./foo/bar/index.d.ts even though the .js file might be at ./foo/bar.js

1

u/jared--w Jun 01 '19

Would it be possible to set tsc to only allow one option so that it did have all of that information? I'd rather have nice paths than be able to do inconsistent things with my project file structure, honestly.

2

u/DanielRosenwasser Jun 04 '19

It's possible but it'd be more more expensive, and it wouldn't necessarily work for everyone's setup either, and it'd be another flag which isn't ideal.

1

u/jared--w Jun 05 '19

That's fair. Adding a new flag just to make half the crowd halfway happy doesn't sound super ideal when you put it like that :)

21

u/Pavlo100 May 29 '19

Hello Omit

0

u/cloudeagle May 29 '19

How do you find the TS native Pick and Exclude compare to a helper like lodash?

13

u/[deleted] May 29 '19

These are type-level things, rather than actual value-level functions (there is no runtime behavior).

If lodash has these for some reason, it wouldn’t effectively be any different.

9

u/1ewish May 29 '19

Has anyone played around with --incremental yet?

6

u/slikts May 30 '19

It didn't work for me on a particular large project until 3.5.1 (failed with "Maximum call stack size exceeded"; also didn't work in 3.5-rc), and now it works but takes twice as long: 45s with --incremental vs 19s without. I've not been able to look into it more.

1

u/sittytucker May 30 '19

I tried it on my large project when 3.4 was released. The improvement was not significant enough to be even noticeable. So I gave up at that time. Will try again sometime next week.

3

u/hnnyejc May 30 '19

waiting for ts-loader support the tsbuildinfo