5 Oct

Running

On Unix (Linux — Ubuntu, etc and macOS) start a terminal and type:

cd /path/to/lab  # navigate to the lab's folder
ghci <lab>.hs

On Windows double-click the <lab>.hs file (make sure you are not working inside an archive!).

Inside GHCi you can enter commands like:

> 3 + 4  -- basic arithmetic
7

> length "hello"  -- built-in function
5

> double 41  -- user defined function in the loaded file
82

:l <other_file>.hs loads another file (short for :load) .

:r reloads the last-loaded file – used after editing it (short for :reload).

Completion is available via tab, command history is via ↑ and ↓.

Exit with ctrl-D, cancel a command with ctrl-C.

Installing at home

haskell.org/platform has installation instructions for Mac, Linux and Windows.

Atom offers syntax highlighting through the haskell-language plugin.

rextester.com provides an online compiler, as a temporary solution.