I tried to install the tuareg mode for emacs on Manjaro, but when i open emacs and create a test.ml file, the "tuareg" menu isn't even there and all the commands such as Ctrl c + Ctrl b are undefined, it's as if tuareg wasn't installed.
In order to install the tuareg mode for emacs here is what i've done :
sudo pacman -S emacs
sudo pacman -S opam
opam install ocaml
opam install tuareg
opam init
Everything worked well during the installation so i don't know why it's not working. I guess it's something like emacs isn't linked to the tuareg mode and i need to specify a folder or something like that to find the tuareg mode. But even then i cant't find the .emacs files, so i don't really know what to do.
You're not far from it !
As you guessed, emacs doesn't know that tuareg exists. The simplest way to solve that is to type:
opam install user-setup
You'll need to restart emacs afterwards to load the new configuration.