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update prolog_parser version, allow ('|') operator in DCGs (#274)

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This commit is contained in:
Mark Thom
2020-02-23 13:16:14 -07:00
parent af23258152
commit 8ba92d8b99
4 changed files with 14 additions and 38 deletions
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19
src/prolog/lib/dcgs.pl
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@@ -1,6 +1,7 @@
% :- op(1105, xfy, ('|')).
:- module(dcgs, [op(1200, xfx, -->), phrase/2, phrase/3]).
:- module(dcgs, [op(1200, xfx, -->),
op(1105, xfy, '|'),
phrase/2,
phrase/3]).
:- use_module(library(lists), [append/3]).
@@ -31,8 +32,8 @@ phrase_((A -> B ; C), S0, S) :-
).
phrase_((A ; B), S0, S) :-
( phrase(A, S0, S) ; phrase(B, S0, S) ).
%% phrase_((A | B), S0, S) :-
%% ( phrase(A, S0, S) ; phrase(B, S0, S) ).
phrase_((A | B), S0, S) :-
( phrase(A, S0, S) ; phrase(B, S0, S) ).
phrase_({G}, S0, S) :-
( call(G), S0 = S ).
phrase_(call(G), S0, S) :-
@@ -95,7 +96,7 @@ dcg_constr([]). % 7.14.1
dcg_constr([_|_]). % 7.14.2 - terminal sequence
dcg_constr(( _, _ )). % 7.14.3 - concatenation
dcg_constr(( _ ; _ )). % 7.14.4 - alternative
%% dcg_constr(( _'|'_ )). % 7.14.6 - alternative
dcg_constr(( _'|'_ )). % 7.14.6 - alternative
dcg_constr({_}). % 7.14.7
dcg_constr(call(_)). % 7.14.8
dcg_constr(phrase(_)). % 7.14.9
@@ -119,9 +120,9 @@ dcg_cbody(( GRCond ; GRElse ), S0, S, ( Cond ; Else )) :-
subsumes_term(( _GRIf -> _GRThen ), GRCond),
dcg_cbody(GRCond, S0, S, Cond),
dcg_body(GRElse, S0, S, Else).
%% dcg_cbody(( GREither '|' GROr ), S0, S, ( Either ; Or )) :-
%% dcg_body(GREither, S0, S, Either),
%% dcg_body(GROr, S0, S, Or).
dcg_cbody(( GREither '|' GROr ), S0, S, ( Either ; Or )) :-
dcg_body(GREither, S0, S, Either),
dcg_body(GROr, S0, S, Or).
dcg_cbody({Goal}, S0, S, ( Goal, S0 = S )).
dcg_cbody(call(Cont), S0, S, call(Cont, S0, S)).
dcg_cbody(phrase(Body), S0, S, phrase(Body, S0, S)).