[m-rev.] for post-commit review: warn about bad coerce arities

[Zoltan Somogyi]

On 2024-05-28 12:56 +10:00 AEST, "Peter Wang" <novalazy at gmail.com> wrote:
> Technically, the user is allowed to name things 'coerce'.
> It's only 'coerce(Expr)' that is parsed as a type conversion expression.

Ok, but should we change that? I think we should.

> Can we change this error into a suggestion such as:
> 
>     A type conversion expression must be written as `coerce(Expr)'.

That is better wording, except I would end with `coerce(Term)'.
I will make the change later today.

Zoltan.