ghc cvs breaks LINE pragma?

John Meacham john at
Sat Dec 13 18:11:28 EST 2003

I use this little script called with 

ghc -pgmF ./drift -F

; cat ./drift
if grep -q '{-!' $2; then
  echo DrIFT $2 -o $3;
  DrIFT $2 -o $3;
  echo "{-# LINE \"$1\" 0 #-}" >> $3
  cat $2 >> $3;

however it seems to have stopped working with ghc cvs rather than 6.01.
it dies with a 'lexical error' on the LINE pragmas generated by the
script and DrIFT.
any idea what the problem is?

PS. on another tangent (although this is is probably a library issue), I
tried modifying my code to use the new Data.Generics rather than
Strafunski, and found that Data could not be derived because instances
for a lot of built in classes don't exist and it is unclear how to write
them by hand. is it possible to retroactivly add a 'deriving' clause to
something that was declared in another unmodifyable module?  or can we
make sure that all predefined (and library) types derive Data?

John Meacham - California Institute of Technology, Alum. - john at

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