Grade-conditional predicates & modes

[Warwick Harvey]

Hi,

With some of the changes I've been making to the Mercury compiler, I have 
come across the desire to have certain library predicates (and certain modes 
of others) only available in some grades of the compiler.

Apart from there being no support for conditional compilation, all grades 
share the same interface files, and so on.

It would seem that adding this kind of feature would require a major 
overhaul, and is more work than the feature is worth to me.  :-)

Does anybody have any comments/ideas/suggestions?

Thanks,
Warwick