5 May
2003
5 May
'03
8:28 a.m.
sashan
When compiled with ghc I get the following error: test.hs:8: No instance for (Num String) arising from the pattern `2' at test.hs:8 In a case alternative: 2 -> do putStrLn "f2" In the case expression: case choice of 1 -> do putStrLn "f1" 2 -> do putStrLn "f2" _ -> do putStrLn ""
Please can someone explain.
The compiler already did: No instance for (Num String) In other words, a String is not a Num(ber), and you are treating it as one (the variable 'choice' in the case clause). -kzm -- If I haven't seen further, it is by standing in the footprints of giants