Package from https://opam.ocaml.org/packages/ is not seen by opam 1.2.2

[guillaumebrunerie]

There is an opam package called lablgtk3 (https://opam.ocaml.org/packages/lablgtk3/) but opam 1.2.2 does not find it.

$ opam install lablgtk3
[ERROR] No package named lablgtk3 found.

According to the documentation of opam (https://opam.ocaml.org/doc/1.2/Usage.html):

If you find a package there but not on your computer, either it has been recently added and you should simply run `opam update`, or it's not available on your system or OCaml version -- `opam install PACKAGE` will give you the reason.

But opam update says that everything is up-to-date and opam install lablgtk3 does not give the reason, so there is a bug somewhere (maybe in the documentation).

Maybe it is because I am using opam 1.2.2 (the version shipped with Ubuntu 18.04, I haven’t tried with a more recent version)? In that case it would be nice to at least write somewhere on the package page (https://opam.ocaml.org/packages/lablgtk3/) that you need opam 2.0.x to install it.

# OPAM config report
# opam-version    1.2.2 
# self-upgrade    no
# os              linux
# external-solver aspcud $in $out $criteria
# criteria        -count(removed),-notuptodate(request),-sum(request,version-lag),-count(down),-notuptodate(changed),-count(changed),-notuptodate(solution),-sum(solution,version-lag)
# jobs            4
# repositories    1 (http)
# pinned          1 (path)
# current-switch  4.06.1
# last-update     2019-08-09 13:47

[hcarty]

The opam 1.2 branch of opam-repository is no longer being updated. You would need to move to opam 2 for the latest package updates. I'm not sure if there is more official documentation on this, but the opam 2.0.0 release writeup talks about the opam 1.2 package branch being maintenance-only: https://opam.ocaml.org/blog/opam-2-0-0/

For Ubuntu 18.04 you should be able to use the latest Linux release build of opam from https://github.com/ocaml/opam/releases (currently https://github.com/ocaml/opam/releases/download/2.0.5/opam-2.0.5-x86_64-linux)

[guillaumebrunerie]

Thank you for the link to the release notes, I had missed that.

Still, it would be nice to have some mention of this fact on https://opam.ocaml.org/packages/

[hcarty]

Completely agreed about having something on the site to indicate that the packages reflect availability under opam 2.x