Cannot get utop and merlin to work with Core and Base

Question

The packages are installed correctly.

opam install core                                    
[NOTE] Package core is already installed (current version is v0.14.1)

opam install base
[NOTE] Package base is already installed (current version is v0.14.1).

My .ocamlinit file has

(* ## added by OPAM user-setup for ocamltop / base ## 3ec62baf6f9c219ae06d9814069da862 ## you can edit, but keep this line *)
(* ## end of OPAM user-setup addition for ocamltop / base ## keep this line *)

#use "topfind";;
#thread;;
#camlp4o;;
#require "core.top";;
#require "core.syntax";;

The really strange thing is - when I startup ocaml's top level using the ocaml command it loads everything up correctly and commands like open Core;; open Base;; work. But they don't work with utop. I get Error: Unbound module Core. Similarly merlin in VS-code gives me red-squiggly lines if I write open Core.

Can someone help me understand what's happening? I can give you more details if they are helpful. I've already looked at all the similar questions that have been asked and none have helped me solve this.

Edit: If it helps, this is the result of opam switch

❯ opam switch

#   switch   compiler                    description
->  4.12.0   ocaml-base-compiler.4.12.0  4.12.0
    default  ocaml-base-compiler.4.12.0  default

So you have two switches. Can you show the important lines of `opam list`? (I tested on my switch and I have no problem with utop and Base) — Lhooq, Jul 04 '21 at 14:57
`opam list` has everything `async`, `core` `base`, `ocamlfind`, `ocamlbuild`, `dune`, a bunch of ppx related libs etc. — Aditya Bhagwat, Jul 04 '21 at 14:59
Before doing `open Base;;` you wrote `#require "base";;`, right? — Lhooq, Jul 04 '21 at 15:00
I'm not required to do that in a .ml file right? `No such package: base` when I do it on `utop` — Aditya Bhagwat, Jul 04 '21 at 15:02
Let us [continue this discussion in chat](https://chat.stackoverflow.com/rooms/234497/discussion-between-lhooq-and-aditya-bhagwat). — Lhooq, Jul 04 '21 at 15:02
Side-comment: if you are requiring `#camlp4o`, you are following an out-of-date tutorial. — octachron, Jul 04 '21 at 20:03

score 2 · Accepted Answer · answered Jul 04 '21 at 15:11

2

utop was not installed with opam but with brew so it couldn't find the libraries.

Remember to always clean all OCaml related things before installing everything with opam or it may break things.

answered Jul 04 '21 at 15:11

Lhooq

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Cannot get utop and merlin to work with Core and Base

1 Answers1