[m-rev.] for review: improve error messages for missing foreign values in foreign_enum pragmas

[Julien Fischer]

Hi,

On Tue, 7 Jun 2016, Julien Fischer wrote:

> For review by anyone.
>
> Improve error messages for missing foreign values in foreign_enum pragmas.
>
> Currently, if a foreign_enum pragma is missing cases in the constructor -
> foreign value mapping we report that there are some missing foreign values 
> but
> do not list the affected constructors unless --verbose-error-messages is
> enabled.  For cases where there are a small number of missing foreign values
> this is a bit irritating as you need to recompile to find out what they are.
> Change the compiler so the error messsage lists upto the first 10 
> constructors
> that do not have a foreign value.
> (If --verbose-error-messages is enabled then we list all of them as before.)

In the absence of any review comments I will commit this one later this
weekend.

Julien.