Ron de Bruijn wrote:
I now have two pieces of information, at least I think so: I need some instance of my an MArray of my datatype Lesson as an elementtype. And I need some way of integrating the IOArray in that definition. Although this statement is completely easy for an experimented Haskellprogrammer, but it isn't for me.
Can somebody please help me with some concrete stuff (I do understand it's better to do it yourself, but I really don't know how to get any further)?
1. Initially it would be simpler to ignore MArray altogether, and just
use IOArray directly.
2. newArray (and newIOArray etc) is a monadic operation, so you have
to use do notation or >>=.
E.g.
module Main where
import IOExts
data Lesson = Lesson String Int Int String String
deriving Show
main = do
test <- newIOArray (0,1) (Lesson "" 0 0 "" "")
...
--
Glynn Clements