Dubious behavior in TH pretty printer

[Stefan O'Rear]

The Template Haskell pretty-printer handles infix/prefix distinction
improperly, causing text generated using it to be unparsable.
Example:

stefan at stefans:~/daanpp$ ghci -fth
   ___         ___ _
  / _ \ /\  /\/ __(_)
 / /_\// /_/ / /  | |      GHC Interactive, version 6.7.20070323, for Haskell 98.
/ /_\\/ __  / /___| |      http://www.haskell.org/ghc/
\____/\/ /_/\____/|_|      Type :? for help.

Loading package base ... linking ... done.
Prelude> :m + Language.Haskell.TH
Prelude Language.Haskell.TH> runQ [| (+) 2 2 |] >>= print . ppr
Loading package template-haskell ... linking ... done.
GHC.Num.+ 2 2

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.)

Stefan