[Haskell-cafe] Re: Profiling nested case

[Simon Peyton-Jones]

| I had similar experiences as you when attempting to write "high
| performance Haskell"; the language makes you want to use high-level
| abstracted functions but the optimizer (while amazing, to be honest)
| seems to miss a few cases that it seems like it should hit.

Ryan, if you find any of these, do please submit them to GHC's Trac bug-tracker. There's a special category for performance bugs.  Small programs of the form "GHC should hit this, but doesn't" are incredibly useful.

Thanks

Simon