On Mon, Apr 02, 2007 at 09:02:41AM +0100, Simon Peyton-Jones wrote:
| I am trying to use the Template Haskell AST system for internal | representation of terms in a derivation library that can output | Haskell or feed directly into a splice. This "bug", unfixed, would | force me to fork the TH pretty printer. What would people think of a | patch changing the behavor to "Always produce parsable output"? (Yes, | I'm offering to implement it.)
Good plan. You may find the function isSymOcc :: OccName -> Bool in OccName.lhs useful
Send us a patch, by all means.
I already sent a patch to the libraries list: http://haskell.org/pipermail/libraries/2007-April/007317.html This also fixes the printign of tilde-patterns. (That said, a new issue has been found - \ ((:) x xs) -> x pprs as \ (:) x xs -> x, incorrectly parend.) I didn't know about isSymOcc (indeed I never saw an OccName.lhs in template-haskell); I implemented it myself with dropWhile and isAlpha. Stefan