Free type constructor after show-translation

[nomeata]

The show translation creates helper function on the top-level of the module, but can mention local type constructors. So this causes an IR type error after show translation:

let a = {
  type A = ?B;
  type B = Int;
  let x : A = ?5;
  debug_show x
};

I found this while trying to write a test case that checks if Show.typ_id (for now simply T.string_of_typ) does the right thing when it sees two cons with the same name; but it does, as it adds the stamp, which is likely global. This is not only relevant for show but also for serialization. But looks good.

We still might want a better way of hash-consing types than T.string_of_typ.

I wonder if @crusso’s #491 fixes this?

[nomeata]

I wonder if @crusso’s #491 fixes this?

Yes it does! :-)

[crusso]

Yes it does but only because it disabled the check (even for abstract cons, which is wrong). However, in future this should work as we'll need to drop the check for cons of kind Def.

[nomeata]

No longer a problem (the IR doesn't have type defs anymore)