Running a Haskell interpreter #

We’ll use the Glasgow Haskell Compiler as our Haskell implementation in the course. There are a number of ways you can access it.

Via the mira timesharing service #

You probably obtained a login for the C part of the course last term. If not, you can do so here. If you’re happy using mira you can continue to do so. After logging in, the Haskell interpreter is available by launching ghci.

Via apps anywhere #

On windows managed desktop systems, you can launch the Haskell platform via apps anywhere.

On your own device #

This may well be preferable to just using a terminal. Your best bet is probably to follow the official instructions and install ghcup and use that to manage installing ghc and any other components. I recommend installing at least ghc and the haskell-language-server (for editor integration).

Editor support #

If you’re running remotely on mira there aren’t a lot of editors available, so you can just use nano. On your own machine, I suppose you already have a favourite editor. Many come with extension packages that make editing Haskell code easier (providing syntax highlighting, inline error checking and so forth).

You don’t need any of this fancy stuff, but it might make programming in Haskell more pleasant.

For VS Code, install the Haskell extension. This will download a bunch of stuff and hook up with your existing Haskell installation so that you get type-checking hints and autocompletion.

For Emacs, I recommend LSP, in particular the lsp-haskell plugin, which provides similar functionality to the VS Code plugin.

For other editors, you might find some helpful pointers here. The best-supported approach is via the language server protocol, which is implemented for Haskell here. They provide some advice on configuring your editor. This server is installable using ghcup on your own device if you’re doing that, unfortunately it’s not available on mira.