0.29.0

CHANGES:

Highlight

• * Support OCaml 5.5 syntax
  (#2772, #2774, #2775, #2777, #2780, #2781, #2782, #2783, @Julow)
  The update brings several tiny changes, they are listed below.

• * Update Odoc's parser to 3.0 (#2757, @Julow)
  The indentation of code-blocks containing OCaml code is reduced by 2 to avoid
  changing the generated documentation. The indentation within code-blocks is
  now significative in Odoc and shows up in generated documentation.

Added

• Added option letop-punning (#2746, @WardBrian) to control whether
  punning is used in extended binding operators.
  For example, the code let+ x = x in ... can be formatted as
  let+ x in ... when letop-punning=always. With letop-punning=never, it
  becomes let+ x = x in .... The default is preserve, which will
  only use punning when it exists in the source.
  This also applies to let%ext bindings (#2747, @WardBrian).

• Support the unnamed functor parameters syntax in module types
  (#2755, #2759, @Julow)

  module type F = ARG -> S

  The following lines are now formatted as they are in the source file:

  module M : (_ : S) -> (_ : S) -> S = N
  module M : S -> S -> S = N
  (* The preceding two lines are no longer turned into this: *)
  module M : (_ : S) (_ : S) -> S = N

Fixed

• Fix dropped comment in (function _ -> x (* cmt *)) (#2739, @Julow)

• * cases-matching-exp-indent=compact does not impact begin end nodes that
  don't have a match inside. (#2742, @EmileTrotignon)

  (* before *)
  begin match () with
  | () -> begin
    f x
  end
  end
  (* after *)
  begin match () with
  | () -> begin
      f x
    end
  end

• Ast_mapper now iterates on all locations inside of Longident.t,
  instead of only some.
  (#2737, @v-gb)

• Remove line break in M with module N = N (* cmt *) (#2779, @Julow)

Internal

• Added information on writing tests to CONTRIBUTING.md (#2838, @WardBrian)

Changed

• indentation of the end keyword in a match-case is now always at least 2. (#2742, @EmileTrotignon)

  (* before *)
  begin match () with
  | () -> begin
    match () with
    | () -> ()
  end
  end
  (* after *)
  begin match () with
  | () -> begin
    match () with
    | () -> ()
  

• * use shortcut begin end in match cases and if then else body. (#2744, @EmileTrotignon)

  (* before *)
  match () with
  | () -> begin
      match () with
      | () ->
    end
  end
  (* after *)
  match () with
  | () ->
    begin match () with
      | () ->
    end
  end

• * Set the ocaml-version to 5.4 by default (#2750, @EmileTrotignon)
  The main difference is that the effect keyword is recognized without having
  to add ocaml-version=5.3 to the configuration.
  In exchange, code that use effect as an identifier must use
  ocaml-version=5.2.

• The work to support OCaml 5.5 come with several improvements:

  • Improve the indentation of let structure-item with the
    [@ocamlformat "disable"] attribute.
    let structure-item means let module, let open, let include and
    let exception.
  • (let open M in e)[@a] is turned into let[@a] open M in e.
  • Long let open ... in no longer exceed the margin.
  • Improve indentation of let structure-item within parentheses:

    (* before *)
    (let module M = M in
    M.foo)
    (* after *)
    (let module M = M in
     M.foo)