[m-users.] Mercury Crash Course

[Julien Fischer]

Hi Dirk,

On Mon, 5 Aug 2019, Dirk Ziegemeyer wrote:

>> Am 05.08.2019 um 10:47 schrieb Mark Brown <mark at mercurylang.org>:
>> 
>>> There are some coverage gaps that I may eventually close:
>>> 
>>> - DCG syntax
>> 
>> You can probably skip those, as they have been all but superseded by
>> state variables.
>
> What do you think about marking DCG syntax as deprecated and remove it
> from the language after a while?

Our current position is that preserving some level of Prolog syntax
compatibility is useful (e.g. for those porting Prolog programs to
Mercury etc.)  That's the main reason DCGs are still supported, as well
as the 'X is Y + Z' syntax for arithmetic and a few other things.

(In the distant past Prolog source compatibility was esssential since
Mercury compiled down to Prolog.

Julien.