cc @Wilfred, @ELLIOTTCABLE for feedback

I'm sure I'd approve (anything that improves readability and negative space, I'm happy with!); but if you want more thorough commentary, would you mind pasting a few examples (input/before-change/after-change) into the Issue? [=

@gpetiot the logic looks good to me! My sample code from #554:

let foo x y =
  do_some_setup x ;
  do_some_setup y ;

  (* This is the important bit *)
  important_function x ;
  another_important_function x y ;

  cleanup x y

Is unchanged with ocamlformat --break-sequences=preserve --enable-outside-detected-project on this PR, which is exactly what I'd hoped for :). I also like that it collapses blank lines:

Before:

let foo x y =
  (* foo *)
  do_some_setup x ;



  cleanup x y

After:

let foo x y =
  (* foo *)
  do_some_setup x ;

  cleanup x y

My only concern is that it doesn't make sense to use --break-sequences here. Whether or not the user wants expressions grouped on a line or not (fit versus all) seems separate to how they want blank lines to be handled.

My only concern is that it doesn't make sense to use --break-sequences here. Whether or not the user wants expressions grouped on a line or not (fit versus all) seems separate to how they want blank lines to be handled.

I tend to agree with that, I will change it so it is a separate option.

Edit: done, I added an option, and there is no diff with test_branch (also tested the jane street profile).

I fixed this and added a test.

This looks like a good candidate for conventional. Collapsing multiple blank lines is good practise in most code.

@avsm can you elaborate? "ocaml avsm conventional" doesn't yield any interesting search-engine results :P

This is the name of a preset profile of ocamlformat, you can use it with --profile=conventional.