Switches are configured with OCAML_TOPLEVEL_PATH but the variable name is OCAMLTOP_INCLUDE_PATH

[dbuenzli]

I was trying to change omod and down to stop pooping omod.top and down.top into ocaml's library directory and leave it for $(opam var lib)/toplevel to handle it.

This should be possible since OCaml 4.08.0 when ocaml/ocaml#7808 was resolved by @nojb's ocaml/ocaml#1841.

Unfortunately the compilers packages set the OCAML_TOPLEVEL_PATH instead of OCAMLTOP_INCLUDE_PATH so that doesn't work.

Not sure exactly who's responsible for opam compiler packages so I tentatively cc @Octachron and @dra27.

# With a down modified to no longer install `down.top` in $(opam var lib:ocaml)

> OCAML_TOPLEVEL_PATH=/Users/dbuenzli/.opam/4.14.2/lib/toplevel ocaml -noinit 
OCaml version 4.14.2
Enter #help;; for help.

# #use "down.top";;
Cannot find file down.top.
# ^D
> OCAMLTOP_INCLUDE_PATH=/Users/dbuenzli/.opam/4.14.2/lib/toplevel ocaml -noinit
OCaml version 4.14.2
Enter #help;; for help.

# #use "down.top";;
Down v0.3.0-5-g8eef77b loaded. Type Down.help () for more info.
# 

[dra27]

Not sure exactly who's responsible for opam compiler packages so I tentatively cc @Octachron and @dra27.

Suggests that I really should move on getting the precise value in dra27@7813e70 sorted out and upstreamed 🙂