desperately seeking RULES help

[Don Stewart]

claus.reinke:
> >Right. There are two things here:
> >
> >   1) -frewrite-rules
> >
> >enables rules to fire.
> >
> >   2) -fglasgow-exts
> >
> >enables parsing of RULES pragmas, and their interpretation.
> >
> >You need both if you wish to both write your own rules, and have them
> >fire.
> 
> nope!-) -fglasgow-exts is sufficient for the RULE to be parsed
> and applied in Lennart's code, -frewrite-rules doesn't seem to
> serve any noticable purpose.

Well, if -O is on, -frewrite-rules is already on by default.
Try -fno-rewrite-rules with -O to turn them off specifically,
or in ghci, -frewrite-rules can be used to help them fire even on
bytecode.

> but i see now this is under re-evaluation, aptly titled:
> 
>    "Confusing flags for rewrite rules"
>    http://hackage.haskell.org/trac/ghc/ticket/2213
>    (see simonpj's comment at the end)

Right.

-- Don