On Fri, Dec 4, 2009 at 9:26 PM, John Moore
Hi, I'm a bit stuck. I want to indent my answer by using a count function to indent my answer. Say for example I want to show the levels in a simple arithmethic expression. like 3*(4+5) I want to be able to print out : 4+5 = 9 3*9 = 27 (notice the indentation as I go through an expression.
I tried this but it a mess, I tried to use prettyprint but this seemed very complicated.
I'm not sure I really understand what your problem is... If you just want to indent a String, it is easy to do with :
indent :: Int -> String -> String indent n s = replicate n ' ' ++ s
If you want to use this with your evaluation of a small arithmetic language, I would suggest making your evaluator returns a list of its reductions (with the Writer Monad maybe) and use :
zipWith indent [2,4..] reductionsList
-- Jedaï