Data/Typeable/Uniplate instances for GHC types

[Simon Peyton-Jones]

I wasn't suggesting changing GHC to *use* generic traversals. Rather, I was suggesting to initially use the simplest available technology to *provide* the possibility of generic operations to clients of the GHC API.  They can choose whether or not to use them.

Simon

| -----Original Message-----
| From: Chaddaï Fouché [mailto:chaddai.fouche at gmail.com]
| Sent: 18 July 2008 15:44
| To: Simon Marlow
| Cc: Simon Peyton-Jones; cvs-ghc at haskell.org; Max Bolingbroke
| Subject: Re: Data/Typeable/Uniplate instances for GHC types
|
| 2008/7/18 Simon Marlow <marlowsd at gmail.com>:
| > That approach worries me.  We could add generic traversals all over the
| > place, and while none of them is a "bottleneck", the overall effect could
| be
| > quite significant.
| >
| > The right approach I believe is to keep an eye on compile times when making
| > these kind of changes, and if at any point the compiler slows down by a few
| > percent, then back off.  Timing a compile of GHC itself is good for this.
| >
|
| I recently added Data and Typeable instance to all AST datatypes
| directly in the code of GHC, the compilation time didn't seem affected
| by this addition. Of course I didn't try to add Uniplate, Term ...
| instances as well.
|
| --
| Jedaï