How to make opam recognize a manually installed OCaml version

[anzhi0708]

Hello!

A few days ago I installed OCaml 4.0.* & OPAM 2.0.* - both are very outdated versions - from some repo, then installed OCaml 4.14.1, which is a newer version, using OPAM.

Then I decided to give OCaml 5 a try,

so I uninstalled both OCaml 4.0.* and OPAM, but seemed like OCaml 4.14.1 was not removed from my device. It was still under ~/.opam; it was installed when I cded into there and typed opam switch create 4.14.1.

Now, I compiled OCaml 5.1.0 from source, manually, on Android, thanks to the good folks here, and I reinstalled OPAM using curl after that.

So, right now, there are two versions of OCaml, 4.14.1 and 5.1.0+dev1.

But OPAM only recognized 4.14.1, I have to type "$PREFIX/bin/ocaml" to run 5.1.0 like this

$ $PREFIX/bin/ocaml --version
The OCaml toplevel, version 5.1.0+dev1-2022-06-09

which is annoying, how can I configure OPAM properly?

Thanks!

---

• Edit:

~/.opam $ eval $(opam env)
~/.opam $ opam switch list
#  switch  compiler
          description
→  4.14.1  ocaml-base-compiler.4.14.1
          4.14.1
~/.opam $
~/.opam $ ocaml --version
The OCaml toplevel, version 4.14.1
~/.opam $ $PREFIX/bin/ocaml --version
The OCaml toplevel, version 5.1.0+dev1-2022-06-09
~/.opam $ which ocaml
/data/data/com.termux/files/home/.opam/4.14.1/bin/ocaml
~/.opam $ echo $PATH
/data/data/com.termux/files/home/.opam/4.14.1/bin:/data/data/com.termux/files/home/apps:/data/data/com.termux/files/home/.opam/4.14.1/bin:/data/data/com.termux/files/home/apps:/data/data/com.termux/files/usr/bin

~/.opam/opam-init $ opam switch 5.1.0+dev
[ERROR] No switch 5.1.0+dev is currently
        installed. Did you mean 'opam switch
        create 5.1.0+dev'?
        Installed switches are:
          - 4.14.1

[kit-ty-kate]

Did you run opam switch <name you used for your 5.1 switch> ? If so, if that didn't change the environment automatically (probably because you didn't accept opam to change your bashrc file during opam init), run eval $(opam env) in the terminal you want to change the environment in.

[anzhi0708]

That 5.1 version was installed from source code, not through OPAM, so I guess that's why OPAM didn't know there's another version there.

~/.opam $ eval $(opam env)
~/.opam $ opam switch list
#  switch  compiler
          description
→  4.14.1  ocaml-base-compiler.4.14.1
          4.14.1
~/.opam $
~/.opam $ ocaml --version
The OCaml toplevel, version 4.14.1
~/.opam $ $PREFIX/bin/ocaml --version
The OCaml toplevel, version 5.1.0+dev1-2022-06-09
~/.opam $ which ocaml
/data/data/com.termux/files/home/.opam/4.14.1/bin/ocaml

[anzhi0708]

I did not give enough information in this discussion; I'm sorry, and I'll close this discussion (since I'm don't know how to delete it) and start a new one with more detailed information.

[kit-ty-kate]

no no don't worry, i was about to reply. I think i understand your issue but I'm currently in a meeting

[kit-ty-kate]

Ok I'll answer in #5483 I guess.