[m-rev.] diff: minor ml_optimize.m improvements

[Zoltan Somogyi]

On Wed, 11 Jan 2017 14:19:59 +1100 (AEDT), "Zoltan Somogyi" <zoltan.somogyi at runbox.com> wrote:
> > It may be useful if we add a new informational message
> > '--inform-incomplete-switch' which prints out where this is happening.
> 
> That is a good idea. I will look into it.

I have implemented a first draft of the option proposed by Julien.
The resulting messages (stage2/*/*.err) are attached.

I think we need to think about limiting the messages somehow.
If a switch unifies X with (say) three function symbols of its type,
but not with the other 97 function symbols in its type, then I think

- either we should not list all the 97 other function symbols in the message, or
- we should not generate a message in the first place.

We should probably have a maximum number of function symbols
we should print in one message (say ten, with the number being
configurable).

We could also have a second configurable threshold: we generate a message
for an incomplete switch only if that switch mentions at least x% of the
function symbols the switched-on var could be bound to at the start of the
switch. (For most switches, this will be the number of function symbols
in the type of the switched-on variable, but it could be restricted further
by the initial inst of the variable.)

There may also be other circumstances in which we may not want
to print a message about an incomplete switch, but I plan to look for those
only after fixing the above.

About the messages themselves: I am pretty sure we should omit
the module qualifiers from the names of the function symbols,
but I am in two minds about whether we should force the messages
to print each function symbol on a line of its own.

Any opinions on any of this? Any proposals for names of the options
that do the configurations mentioned above?

Zoltan.



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