How to practice OCaml with Learn-OCaml

If you are a student that wants to know how to setup your environment to practice your OCaml skills with Learn-OCaml, this tutorial is for you. There are two ways to use the Learn-OCaml system: in web application, directly on the browser (hence, wit zero configuration) ; or with a command line tool named learn-ocaml-client.

Using Learn-OCaml in the browser

Your teacher must have provided an URL for the Learn-OCaml instance used in your OCaml course. Then, to start using the platform:

Important note: Write down your token! This is the information that will allow you to recover your session from another machine.

Using Learn-OCaml from the command line

As an experienced programmer, you probably want to use your favorite editor (Emacs, Vim, Atom, VSCode, etc) to program in OCaml. This is possible thanks to our command line tool named learn-ocaml-client! Yet, it requires more efforts in terms of setup. Maybe your teacher already installed learn-ocaml-client on the computer lab machines.

Installation of learn-ocaml-client

There are two methods to install learn-ocaml-client.

Method 1: Using opam

If you are already using the OCaml package manager OPAM, simply do:

opam install learn-ocaml

Method 2: Compiling learn-ocaml by hand

Note: you need a working opam environment (at least 2.0.0~rc2).

Using learn-ocaml-client

Initializing configuration file

The first time you run learn-ocaml-client, you will be asked for the URL of the Learn-OCaml instance you want to use and you will also be asked to enter your nickname and your token.

Once this is done, this information is stored in the file ~/.config/learnocaml/client.json so that you do not have to enter it anymore. If you want to change this configuration, remove this file and the client will recreate it the next time it is launched.

Practicing your OCaml skills with the client

learn-ocaml-client allows you to submit the content of a file as an answer to an exercise of the Learn-OCaml instance. This answer will be graded and saved onto the server, exactly as in the web application.

The first thing to do is to get the identifier of the exercise you want to work on. This identifier is written on the webpage of the server.

The, let us assume that the exercise identifier is exercise1 and that you have written an answer in the file named myanswer.ml, you can submit your answer from the command line by:

learn-ocaml-client --id=exercise1 myanswer.ml

As a response, you will obtain a grading report of the following form: