Hi,

I'm right at the start of learning Haskell, and I decided to jump from reading LYAH to writing a simple real-world program.

It's based very closely on https://github.com/haskell-hvr/cassava/blob/master/examples/NamedBasedGeneric.hs (I removed the bit that constructs the test file, as I already have a file), and I've done "cabal install cassava", first as root, and then when I first go the error, as myself using the sandbox (which didn't change the output).  I first tried this with running ghc directly, and then followed the instructions on https://wiki.haskell.org/How_to_write_a_Haskell_program, and all these get the same errors:

Main.hs:4:1: error:
    Could not find module ‘Data.Csv’
    Locations searched:
      Data/Csv.hs
      Data/Csv.lhs
      Data/Csv.hsig
      Data/Csv.lhsig
  |
4 | import Data.Csv
  | ^^^^^^^^^^^^^^^

Main.hs:6:1: error:
    Could not find module ‘Data.Vector’
    Perhaps you meant Data.Functor (from base-4.11.1.0)
    Locations searched:
      Data/Vector.hs
      Data/Vector.lhs
      Data/Vector.hsig
      Data/Vector.lhsig
  |
6 | import qualified Data.Vector as V
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

I don't understand the connection between the name "cassava" and "Data/Csv", although looking around in the directories that have been produced, I see that Data/Csv is within the cassava directories.   I'd like not only to know how to fix this,  but also a pointer for what I should look at to understand what is going on.

This is on a Debian system.

thanks,

__John (completely new to Haskell, experienced in C, Lisp, Python and others, if that helps to pitch the level of answers)