patch applied (ghc): Adding a GENERATED pragma

[Simon Peyton-Jones]

Andy: if GENERATED stays, can you document it in the user manual please?
LINE is documented at 7.10.5


| -----Original Message-----
| From: Andy Gill [mailto:andy at galois.com]
| Sent: 29 December 2006 23:18
| To: Duncan Coutts
| Cc: Simon Peyton-Jones; cvs-ghc at haskell.org
| Subject: Re: patch applied (ghc): Adding a GENERATED pragma
|
| >
| > LINE can already refer to an external non-.hs file. This is exactly
| > how
| > things works now with all manner of pre-processors, alex, happy,
| > cpphs,
| > c2hs, hsc2hs, etc.
| >
| > I don't quite have an intuition for this yet, can you give an
| > example of
| > how this more fine grained pragma works and some use-case not
| > currently
| > covered by LINE?
| >
|
| Ahhh. LINE does? Oh.
|
| - GENERATED works on an expression based level, and can specify
| specific spans.
|    (20:4 - 21:8, for example).
|   - GENERATED is a true pragma; it hints where things come from, but
| does not change
|    the error message. I want the Haskell source spans to remain
| unchanges.
|
| But perhaps a variant of LINE would be a better name.
|
| Andy