Dune says "unbound module ounit2"

Learning
1

I am writing my first small program with Ocaml and dune. It was going okay, until I discovered Ounit2 and tried to use it. I think I have gone through the proper steps:

  1. Installed ounit2 with “opam install ounit2”.
  2. Added ounit2 to my dune file in the test directory:
    (test
    (name test_ltc)
    (libraries lib ounit2))
  3. Put 'open Ounit2" at the top of test.ltc.ml

But ‘dune build’ says ‘unbound module Ounit2’.

I can’t spot my mistake. Help!

2

Check the capitalization of the module name?

OUnit2
.
(I did the same thing. Multiple times.)

3

!!!
I feel so stupid. Thank you.

4

Welcome to the club!

1 Like
5

Oh. I forgot to change the capitalization in the dune file. It stills says:
(test
(name test_ltc)
(libraries lib ounit2))

But it doesn’t cause an error. I’d think it should be “oUnit2”. Is this dune phrase not case sensitive at all? (I’m still learning dune.)

6

Don’t. The computer is inhumane. This is an obvious case where spell-checking should be applied (“Did you mean?”).

This is a library name (a.k.a ocamlfind package name, sadly it’s a bit complicated, read here). These names are usually lowercase, you can check them out with ocamlfind list.