Re: debugging

[Kwanghoon Choi]

> 
> Indeed. In earlier GHC versions there was the Trace library with the
> `trace' function. 
> Where it is now?

IOExts.hs has trace function. Your program has to import IOExts module.
When compiling using GHC, the option "-fglasgow-exts" must be given.
I hope that there will be some standard way to use non-standard function
`trace' among Haskell compilers.

Kwanghoon Choi