Go to https://www.haskell.org/ and download it.
Once installed, open a terminal, and type
That would start up the Haskell interpreter. Now you can type “1 + 2” to evaluate it. To exit, type “exit”.
Run a Haskell Program
Creat a file “test.hs” and in it put:
fac :: Integer -> Integer fac 0 = 1 fac n | n > 0 = n * fac (n-1) main = print (fac 3)
Now, in terminal, cd to the same directory the file is at, start ghci, and type:
:load test.hs fac 3
You will see it's output is 6.
In ghci, commands to the interpreter are prefixed with a colon “:”. The command “load” loads a file. To see other commands, type “:help”.