Re: [Caml-list] How can I change the margin size in the toplevel?

[Gabriel Scherer <gabriel.scherer@gmail.com>]

For the record, Simon Cruanes is trying to find a good fix for the
issue, with a preliminary patch proposal in
  https://github.com/ocaml/ocaml/pull/207
Maybe we could discuss the implementation there (or in a new Mantis
ticket) rather than on the mailing-list directly.

(There are wonderful people that prepare summaries of mailing-list
discussions, you know, they probably have to read all the messages,
let's not create too much work.)

On Wed, Sep 23, 2015 at 6:05 PM, Alan Schmitt
<alan.schmitt@polytechnique.org> wrote:
> On 2015-09-23 14:23, Alan Schmitt <alan.schmitt@polytechnique.org> writes:
>
>> Is there a guide somewhere that explains how to create a new opam switch
>> From local (modified) ocaml sources?
>
> A very helpful colleague gave me a crash course on nix and I was able to
> compile a patched version (where I tweaked error_of_printer in
> parsing/location.ml as follows):
>
> #+begin_src ocaml
> let error_of_printer loc print x =
>   let buf = Buffer.create 64 in
>   let ppf = Format.formatter_of_buffer buf in
>   Format.pp_set_margin ppf (Format.pp_get_margin !formatter_for_warnings ());
>   pp_print_string ppf "Error: ";
>   print ppf x;
>   pp_print_flush ppf ();
>   let msg = Buffer.contents buf in
>   errorf ~loc "%s" msg
> #+end_src
>
> This works great: I can now change the margin of the error messages
> simply by doing a "Format.set_margin" in the toplevel.
>
> Alan
>
> --
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