{-# LINE 100 "Foo.hs #-} vs. # 100 "Foo.hs"

[Marcin 'Qrczak' Kowalczyk]

What should be the preferred way of marking correspondence to source
positions after some preprocessing?

Here is what is currently supported:

                        | {-# LINE 100 "Foo.hs #-}     | # 100 "Foo.hs"
------------------------+------------------------------+----------------
Released ghc, no   -cpp | understand                   | error
Released ghc, with -cpp | understand                   | understand
Developed ghc           | understand                   | understand
hbc                     | understand (ignore filename) | understand (warning)
Hugs                    | ignore                       | error
Released nhc98          | error                        | understand
Developed nhc98         | ignore                       | understand

I would choose LINE pragma. In this case nhc98 should be taught
about it.

-- 
 __("<  Marcin Kowalczyk * qrczak@knm.org.pl http://qrczak.ids.net.pl/
 \__/
  ^^                      SYGNATURA ZASTĘPCZA
QRCZAK