Utop sends "Alert deprecated: module Base.Format"

Learning
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1

Hi,

On this page Real World OCaml, I tried to follow the instructions to :

  1. Install and set up opam
  2. Install librairies and tools
  3. Set up my editor (I use Emacs)

The step 2) asks me to execute this command :

opam install core core_bench utop

Then I have to set up “utop”, by creating the file "~/.ocamlinit ", and insert the following contents :

#require “core.top”;;
#require “ppx_jane”;;
open Base;;

The step 3) asks me to execute this commands :

opam install user-setup tuareg ocamlformat merlin
opam user-setup install

But when I launch “utop”, this message appears :

Welcome to utop version 2.13.1 (using OCaml version 4.13.1)!

File “/home/asalek01/.opam/4.13.1/lib/toplevel/topfind”, line 20, characters 12-33:
20 | let fmt = Format.make_formatter (fun _ _ _ → ()) (fun _ → ()) in
^^^^^^^^^^^^^^^^^^^^^
Alert deprecated: module Base.Format
[2016-09] this element comes from the stdlib distributed with OCaml.
[Base] doesn’t export a [Format] module, although the
[Caml.Format.formatter] type is available (as [Formatter.t])
for interaction with other libraries.

Does anyone knows why ?

2

AFAIR, either the recent version of base, or the recent version of core gives this deprecation. You should try to install the older versions of these libraries, and check.

3

Thank you for your response @Kakadu . By looking the content of the file “~/.ocamlinit”, I read this:

#require “core.top”;;
#require “ppx_jane”;;
open Base;;
(* ## added by OPAM user-setup for ocamltop / base ## 3ec62baf6f9c219ae06d9814069da862 ## you can edit, but keep this line )
#use “topfind”;;
( ## end of OPAM user-setup addition for ocamltop / base ## keep this line *)

Finaly, I decided to write the line “open Base;;” after “#use "topfind";;” :

#require “core.top”;;
#require “ppx_jane”;;
(* ## added by OPAM user-setup for ocamltop / base ## 3ec62baf6f9c219ae06d9814069da862 ## you can edit, but keep this line )
#use “topfind”;;
( ## end of OPAM user-setup addition for ocamltop / base ## keep this line *)
open Base;;

Then I relaunch “utop” and everything works :

Welcome to utop version 2.13.1 (using OCaml version 4.13.1)!

Findlib has been successfully loaded. Additional directives:
#require “package”;; to load a package
list;; to list the available packages
#camlp4o;; to load camlp4 (standard syntax)
#camlp4r;; to load camlp4 (revised syntax)
#predicates “p,q,…”;; to set these predicates
Topfind.reset();; to force that packages will be reloaded
#thread;; to enable threads

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