Making Mercury code conditional on the grade?

[Warwick HARVEY]

Hi,

I was wondering if there was a convenient way to make Mercury code depend on
the grade with which it is compiled?  Currently I've just created a new
predicate, implemented using a pragma c_code, which uses an appropriate
#ifdef to do the (in this case trivial) piece of work which is conditional.

Is there a better (or an "approved") way of doing this kind of thing?  (E.g.
am I ignorant of some feature which makes it easy?)

Thanks,
Warwick