mirror of
https://github.com/Mercury-Language/mercury.git
synced 2026-04-23 05:13:48 +00:00
401298c013
Estimated hours taken: 2 Make the syntax for defining modes and insts similar to type equivalence. Old syntax: :- inst foo = someinstdefn. :- mode foo :: someinst -> someotherinst. New syntax: :- inst foo == someinstdefn. :- mode foo == someinst >> someotherinst. The old syntax is still supported. For `::' and `->' it may eventually be phased out (but it doesn't cause many problems apart from possible confusion of users, so it's a low priority). In the case of `:- inst' we could already use `==' or `=', however we now make `==' the standard syntax. Again, we support both and probably will for quite some time. NEWS: Mention these changes. compiler/prog_io.m: Make `==' the standard operator for `:- inst <InstDefn>.' declarations. Make `==' and `>>' the standard operators for `:- mode foo == someinst >> someotherinst'. `::' and `->' are still supported. compiler/prog_io_util.m: Make `>>' the standard operator for inline mode declarations. `->' is still supported. doc/reference_manual.texi: Update the syntax in the reference manual. Mention that `::' and `->' is deprecated. tests/valid/Mmakefile: tests/valid/mode_syntax.m: Add a new test of the new syntax. compiler/fact_table.m: Fix a typo (missing quote) in the verbose messages for fact tables.
55 lines
928 B
Mathematica
55 lines
928 B
Mathematica
%
|
|
% This is a test of the mode syntax.
|
|
%
|
|
% The official new syntax is:
|
|
%
|
|
% :- mode foo == bar >> baz.
|
|
%
|
|
% We also accept:
|
|
%
|
|
% :- mode foo :: bar -> baz.
|
|
%
|
|
% which is the old syntax.
|
|
%
|
|
% And finally we accept mixing them up:
|
|
%
|
|
% :- mode foo == (bar -> baz).
|
|
% :- mode foo :: bar >> baz.
|
|
%
|
|
% You can also use `bar >> baz' inline after a mode qualifier.
|
|
%
|
|
|
|
|
|
:- module mode_syntax.
|
|
:- interface.
|
|
:- import_module list.
|
|
|
|
:- mode my_input_list_skel == list_skel >> list_skel.
|
|
:- mode my_output_list_skel :: free >> list_skel.
|
|
:- mode my_list_skel_output == (list_skel -> ground).
|
|
:- mode another_mode :: list_skel -> list_skel.
|
|
|
|
:- pred p is semidet.
|
|
|
|
:- pred p2(list(T)::my_output_list_skel) is nondet.
|
|
|
|
:- implementation.
|
|
|
|
:- pred q(list(T)::list_skel >> list_skel /* my_input_list_skel */).
|
|
:- pred r(list(T)::my_output_list_skel).
|
|
|
|
q(_X) :- q([]).
|
|
r(X) :- r(X).
|
|
|
|
p :-
|
|
r(X),
|
|
q(X).
|
|
|
|
p2(X) :-
|
|
r(X),
|
|
q(X)
|
|
;
|
|
r(X),
|
|
q(X).
|
|
|