[m-rev.] for review: delete references to Erlang in the compiler

[Julien Fischer]

Hi Zoltan,

On Wed, 28 Oct 2020, Zoltan Somogyi wrote:

> 2020-10-28 10:57 GMT+11:00 "Peter Wang" <novalazy at gmail.com>:

>> The major difference with my patch series is that I kept lang_erlang
>> around. The compiler would continue to accept pragma foreign_code,
>> foreign_type, etc. for a language "Erlang" but silently discard them.
>> The compiler would also continue to accept --libgrades-exclude erlang.
>> My plan was that we would leave these transition measures in place for
>> one or two major releases (six or 12 months).
>
> Sorry, but I don't see any point in that. Anyone who wants to keep using
> the Erlang grade would have to keep using pre-erlang-deletion
> compilers anyway, as fitting punishment for not speaking up on m-users.
> Anyone who has never used Erlang would not have any Erlang code
> to delete. The only people affected by the decision here are people
> who used Erlang in the past, but do not use it now. They would have to
> delete any Erlang code at some point in time; I don't see any benefit
> to letting them keep it for a while. To my mind, the simplest thing to do
> would be to stop supporting Erlang in *all* aspects at the same time.

That's true for foreign_code etc; however non erlang grade users may
have --libgrades-exclude erlang in their Mercury.options file (i.e.
becaue the current compiler breaks with the erlang grade when doing 
make install.)

Julien.