Claus Reinke wrote:
f x y z | x
--------------------- $ /cygdrive/d/fptools/ghc/ghc/stage2-inplace/ghc.exe --interactive Debug.hs -ignore-dot-ghci GHCi, version 6.11.20081122: http://www.haskell.org/ghc/ :? for help Loading package ghc-prim ... linking ... done. Loading package integer ... linking ... done. Loading package base ... linking ... done. Loading package ffi-1.0 ... linking ... done. [1 of 1] Compiling Main ( Debug.hs, interpreted ) Ok, modules loaded: Main. *Main> :break f Breakpoint 0 activated at Debug.hs:(1,0)-(2,24) *Main> f 3 2 1 Stopped at Debug.hs:(1,0)-(2,24) _result :: a = _ [Debug.hs:(1,0)-(2,24)] *Main> :list vv 1 f x y z | x
:step Stopped at Debug.hs:1:10-12 _result :: a = _ [Debug.hs:1:10-12] *Main> :list 1 f x y z | x
Looks like a bug to me, At this location the x a y should be
observable and cought in trace history.
It actually looks very similar to bug I reported here:
http://hackage.haskell.org/trac/ghc/ticket/2740
Notice that if you write your function like this (as I mostly do):
f x y z =
if x