Add preprocess to the adapter-static code example

[stiegi]

Without preprocess you get "unexpected token" errors when importing types, as described here: https://stackoverflow.com/questions/72846408/sveltekit-typescript-parse-error-when-importing-types/72846510#72846510

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[dummdidumm]

We probably should use vitePreprocess here to be in line with the starter template

[gtm-nayan]

Which example are you referring to specifically? I don't think we have any snippet that necessitates a preprocessor on that page.

[eltigerchino]

https://kit.svelte.dev/docs/adapter-static#usage
This is the page and section referred to.

[dummdidumm]

I think the problem is that people just copy this verbatim without knowing that they might to adjust things if they are using a preprocessor, and then getting confused by that.
On the other hand, if someone who chose to not use TypeScript at all then they have the reverse problem of svelte-preprocess not being installed, and also being confused. So we either have a short comment there instead like // add preprocessor, if necessary (when you want to use TS, for example), or just leave it be.

[gtm-nayan]

The example configs differ quite a bit already from what's in the templates, export default config vs export default {, not having the JSDoc etc, and drawing a line for upto where these examples should be copy-pastable isn't easy.

showing a diff would likely be more helpful for highlighting the relevant changes, but even then the snippet says the values there are default options so wouldn't really expect people to be copying it

[stiegi]

I think it would be good enough to have a comment that mentions the preprocess.
The problem with this is, for a newcomer, the error message you get will make no sense and it is hard to go from that type error message to the missing preprocessor in the config file. So a hint that specifically targets typescript users might help a lot for newcomers imo

[Rich-Harris]

Thanks for the PR but I'm against this change — as has been pointed out, it's just as likely that people will add an unwanted preprocessor as that they'll remove one they need. Adding something irrelevant to the code sample just obscures the bit we need to communicate.

If developers blindly copy and paste code, errors like this one will be the least of the problems caused!

We could argue that the error message itself should be more informative in this case, but that's a separate conversation