# Custom Set Create a custom set type. Sometimes it is necessary to define a custom data structure of some type, like a set. In this exercise you will define your own set. How it works internally doesn't matter, as long as it behaves like a set of unique elements. ## Getting Started For installation and learning resources, refer to the [exercism help page](http://exercism.io/languages/ocaml). ## Installation To work on the exercises, you will need `Opam` and `Core`. Consult [opam](https://opam.ocaml.org) website for instructions on how to install `opam` for your OS. Once `opam` is installed open a terminal window and run the following command to install core: ```bash opam install core ``` To run the tests you will need `OUnit`. Install it using `opam`: ```bash opam install ounit ``` ## Running Tests A Makefile is provided with a default target to compile your solution and run the tests. At the command line, type: ```bash make ``` ## Interactive Shell `utop` is a command line program which allows you to run Ocaml code interactively. The easiest way to install it is via opam: ```bash opam install utop ``` Consult [utop](https://github.com/diml/utop/blob/master/README.md) for more detail. ## Feedback, Issues, Pull Requests The [exercism/ocaml](https://github.com/exercism/ocaml) repository on GitHub is the home for all of the Ocaml exercises. If you have feedback about an exercise, or want to help implementing a new one, head over there and create an issue. We'll do our best to help you! ## Submitting Incomplete Solutions It's possible to submit an incomplete solution so you can see how others have completed the exercise.