[m-users.] "operator precedence error" - Mercury bug?

[Volker Wysk]

Am Samstag, den 12.10.2019, 20:00 +1100 schrieb Julien Fischer:
> Hi Volker,
> 
> On Sat, 12 Oct 2019, Volker Wysk wrote:
> 
> > This simple module won't compile:
> > 
> > :- module test1.
> > :- interface.
> > :- import_module char.
> > :- pred f(char::in) is semidet.
> > 
> > :- implementation.
> > 
> > f(A) :-
> >    A = '/'.
> 
> You need to escape that using parentheses.
> 
>     f(A) :-
>        A = ('/').
> 
> Otherwise the compiler will treat that as the '/' operator.
> (Mercury doesn't have a specific syntax for character literalsm,
> they're
> just atoms.)

Hmm.. Couldn't find it in the Language Reference Manual.

It turns out that the single quotes are redundant:

f(A) :- 
   A = (/).


Thanks for explaining.
Volker