Any reason why enums are discouraged?

[raythurnvoid]

When trying to use enums inside svelte components you get this message:

TypeScript language features like enums are not natively supported, and their use is generally discouraged. Outside of <script> tags, these features are not supported. For use within <script> tags, you will need to use a preprocessor to convert it to JavaScript before it gets passed to the Svelte compiler. If you are using vitePreprocess, make sure to specifically enable preprocessing script tags (vitePreprocess({ script: true }))|

Is there any reason why they are discouraged? I'm not aware that the Typescript team is discouraging them at all.

Also i think there's a typo in the message:

Outside of <script> tags

should be

Inside of <script> tags

[brunnerh]

TypeScript added language features like enum which do not exist in JS, over the years they moved to only adding types for native JS features and only those that are actually pretty advanced in the standardization process (see the mess that experimental decorators has created).

So enum is being discouraged because it's non-standard and requires a TS compilation step.

The message should be correct.
Code within the <script> tag can be pre-processed with tools like vitePreprocess.
Code outside the <script> tag (e.g. in something like onclick={() => { ... }}) is not treated this way, here types are only erased, so features like enum declarations cannot work there.

[raythurnvoid]

Yeah i expected this reason (not being part of standard js), but Svelte itself is not part of standard JS so not really conviced by this.

I would understand something like: Because we need to run tsc at build time and it can get slow, so they are discouraged for build performance reasons

Thanks for this calrification tho:

Code within the <script> tag can be pre-processed with tools like vitePreprocess.
Code outside the <script> tag (e.g. in something like onclick={() => { ... }}) is not treated this way, here types are only erased, so features like enum declarations cannot work there.

Did not know about that