hartthoma@linuxpt:~>cat test.hs import Debug.Trace foo = foldl (\first second -> (trace ( "first: " ++ ( show first) ) first) + (trace ( "second: " ++ (show second) ) second) ) 0 [1,2,3] bar = foldl (+) traceIt x = trace ("\nTraceIt:\n"++show x++"\n") x hartthoma@linuxpt:~>ghc -e foo test.hs first: 0 second: 1 first: 1 second: 2 first: 3 second: 3 6 hartthoma@linuxpt:~> hope this helps. Ian Duncan <iand675@gmail.com> Sent by: haskell-cafe-bounces@haskell.org 08/16/2007 08:20 PM To haskell-cafe@haskell.org cc Subject [Haskell-cafe] Looking at program execution Is there any way to view the steps that a haskell program goes through step by step? I'm thinking something similar to what I've seen in things I've been reading. For example: foldl (+) 0 [1..10] => (0+1) => ((0+1)+2) => (((0+1)+2)+3) => etc. I've seen these sorts of line-by-line execution steps, but I was curious if there was any way to simply type in a function and its arguments and have ghci or hugs or something print out this sort of visual representation of what's going on. Anyone know of something like this? _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe --- This e-mail may contain confidential and/or privileged information. If you are not the intended recipient (or have received this e-mail in error) please notify the sender immediately and destroy this e-mail. Any unauthorized copying, disclosure or distribution of the material in this e-mail is strictly forbidden.