To install ocaml-merlin, run the following command in macOS terminal (Applications->Utilities->Terminal)
sudo port install ocaml-merlin
To see what files were installed by ocaml-merlin, run:
port contents ocaml-merlin
To later upgrade ocaml-merlin, run:
sudo port selfupdate && sudo port upgrade ocaml-merlin
Reporting an issue on MacPorts Trac
The MacPorts Project uses a system called Trac to file tickets to report bugs and enhancement requests.
Though anyone may search Trac for tickets, you must have a GitHub account in order to login to Trac to create tickets.