Big thank you to the HLS team, and a quick question

[levans]

I just feel compelled to thank the HLS team for 2.8.0.0 in particular.

I have quite a large project with multiple build products and using HLS up until now has not been a great experience in my case. I still soldiered on and got some value from it, but it would be only minutes before it got 'confused' and most of the valuable features stopped working. Now, with 2.8.0.0 I'm really starting to feel like I have the full intended power at my fingertips and I'm really seeing the value of HLS manifest for me! So... thank you so much HLS team for your perseverance and dedication to the goal of giving us, the Haskell community, a world-class development environment that puts our beloved language up there with the other popular languages in terms of development tooling.

Now, my quick question...
I would love to lean into the automatic import management of HLS, but I have some quibbles with how it seems to work atm.
I'm a bit of a stickler for maintaining my import lines sorted lexicographically, and then also for the explicit symbol list to be similarly sorted. I find this helps me more quickly find where I may or may not have imported something.
At this time, it doesn't appear that there's an option to have HLS do this automatically, so if it does have to add either a new module, or a new symbol, I end up having to revisit the list and tidy things up to my satisfaction. So...

Are there any options to turn on the ordering of imports?

I suppose my perfect world would also be to be able to separate the import list into two blocks - first the imports from external libraries and then the 'local' imports (for any modules in my actual project package). The latter tend to be shorter names, often just a single module name and no 'path') and I also like the convenience of quickly finding those imports concerning my own project code, versus from all the dependences.

[jhrcek]

Thank you for your kind words!
I expect the reliability will improve even more once the multiple home units supports (shipped in cabal 3.12) lands.

As for your question:
there's no "ordering of imports" feature built into hls per se, but you can still get it through hls' integration with several popular code formatters (see https://haskell-language-server.readthedocs.io/en/stable/features.html#formatting for which formatters are supported). In hls settings you can pick your preferred formatter and in vscode, there is a "format document" command (I usually invoke it using ctrl+shift+i) which formats the source code of the opened document.
You might want to experiment which formatter suites your preferences the best.
I know that at least ormolu, fourmolu and stylish-haskell provide features for ordering imports (and import lists for each module).

• sylish-haskell is relatively conservative but can order imports alphabetically
• ormolu is opinionated and doesn't provide many options to tweak the resulting format (by design)
• fourmolu allows you to tweak some options using fourmolu.yaml (this is my preferred choice). In hls there's an option to either use relatively recent version of fourmolu compiled into hls binary itself as a library, or you can tweak hls config to enable usage of external formolu binary by setting absolute path (desirable, as the output of formatter evolves with each version and can be annoying when multiple people work on the same project, each of them having different version of fomrolu).

I think all of them respect grouping of imports (i.e. you can have bunch of "external imports" grouped together, separated by empty line followed by your local imports grouped together and running formatter only sorts imports within respective group). In our work codebase we do exactly that and fourmolu preserves that grouping.

[levans]

Thanks for the comprehensive suggestions and comparisons of the various formatters.

I've tended to shy away from formatters in favour of manual formatting, no doubt with various preferences and foibles per my personal aesthetic, and I've always been afraid that formatters would disappoint me one way of the other, but that actually means that I've never tried them, and therefore I may be doing them a huge disservice (especially formulu it seems - given its apparent configurability). So, given that LHS doesn't yet know how to discretely maintain ordered/organized import lists, I'll give these a go and see if I can get comfortable with using one of them. Thanks again.