[Haskell-beginners] GHC warnings

[Emanuel Koczwara]

Hi,

  Why GHC doesn't tell me such things like hpaste? (example here:
http://hpaste.org/82917)
  
27:12: Error: Use replicateM
Found:
  sequence $ replicate gridSize getLine
Why not:
  Control.Monad.replicateM gridSize getLine


50:14: Warning: Use list comprehension
Found:
  if y > 0 then [(UP, (x, y - 1))] else []
Why not:
  [(UP, (x, y - 1)) | y > 0]


81:1: Error: Eta reduce
Found:
  sortByPathCost p ps = sortBy compareHeuristic ps
Why not:
  sortByPathCost p = sortBy compareHeuristic


  Can I enable this kind of verbosity in GHC somehow?

Emanuel