[m-users.] things

[Zoltan Somogyi]

On Thu, 16 Apr 2026 22:33:27 +0200, Tomas By <tomas at basun.net> wrote:

> On Thu, 16 Apr 2026 22:21:40 +0200, Zoltan Somogyi wrote:
> > I *think* that you are expecting the lambda to be polymorphic.
> > That cannot happen; lambdas are monomorphic.
> 
> Yes, but is that meaning/use-ful for programmers using the language,
> or is it just easier to implement...

Lambdas are intended for situations in which you want to construct
a higher order value for a SINGLE CALL. What would be the point of
making them polymorphic?

However, if you feel that polymorphic lambdas would be worth implementing,
you are welcome to implement it yourself. If you send us the diff, I will
review it, and it to the Mercury compiler if it works.

> > The lambda here is also unnecessary; library module that defines
> > the maybe type also defines maybe_is_yes
> 
> Ok, good, will have a look at that.
> 
> > As for the other issue you raised, I still see no
> > - ACTUAL CODE, or
> > - ACTUAL ERROR MESSAGE.
> 
> No but I do not have it easily available.

Knowing that fact does not help me to understand the problem
you are trying to report.

> I think the problem as it appeared to me was that a procedure declared
> in a sub-module interface section was not visible in the parent
> module without the implementation section also being imported.

There is no such thing as "importing an implementation section".

Do you mean to say that you forgot to import a submodule of your parent
module that was included in the parent's implementation section"?

Zoltan.