[m-users.] Mercury Crash Course

[Mark Brown]

On Tue, Aug 6, 2019 at 1:57 AM emacstheviking <objitsu at gmail.com> wrote:
>>
>>
>> >> - 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 You can probably skip those, as they have been all but superseded by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?
>>
>
> Can somebody explain how state variables supercede DCG sytax please...I vaguaely get the destructive in / unique out concept but I am confused now!
>

These are syntactic transformations that are orthogonal to questions
of uniqueness, so I think you may have already been confused (although
I note that the examples in the reference manual have elided the mode
declarations, which otherwise may have helped to clarify this point).

Mark