[m-users.] Modes.

[Zoltan Somogyi]

On Mon, 3 May 2021 10:24:56 +0100, "Sean Charles (emacstheviking)" <objitsu at gmail.com> wrote:
> I am reading code, in the file eqneq.m by Ralph Becket, in the samples folder
> 
>     samples/solver_types/eqneq.m
> 
> mentions is made of the modes ::ia and ::oa but I cannot find them in the reference manual?!

They are defined in builtin.m in the Mercury standard library
as synonyms for an initial/final pair of instantiation states.
The reference manual defines those instantiation states
in section 16, which discusses solver types, which are
Mercury's support for writing constraint solvers.
They are intended for use by experts in both Mercury
and constraint solving.

I would strongly advise that you look into solver types, if at all,
only after you have strong grasp on the rest of Mercury.
Looking at them now would only complicate learning
all the other aspects of Mercury.

Zoltan.