[mercury-users] maybe(T)

[Ralph Becket]

Michael Day, Monday, 21 October 2002:
> 
> > Yes.  Well, close enough anyway.  We use a pointer to T to represent
> > yes(T) and we use a pointer with value "1" to represent no.
> 
> Actually I made a mistake, the maybe(T) type has "no" as its *first*
> functor, not the second.  Does this affect its representation?

Maybe :-)

I believe that the compiler reserves a number of "impossible"
pointer values as representations for situations like these, so it might
be the case that the actual representation of `no' is slightly
different, but not materially.  Fergus?

Is this an issue you have to deal with or just a point of interest?

- Ralph
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