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Merge pull request #2681 from hurufu/remove-dcgs-that-have-failed-to-expand

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Remove DCGs that have thrown an exception during term expansion
This commit is contained in:
Mark Thom
2024-12-25 14:29:38 -07:00
committed by GitHub
parent afc7b74bbd a599a11169
commit d57f871a12
5 changed files with 19 additions and 2 deletions
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7
src/lib/dcgs.pl
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@@ -214,10 +214,13 @@ dcg_cbody(( GRIf -> GRThen ), S0, S, ( If -> Then )) :-
dcg_body(GRIf, S0, S1, If),
dcg_body(GRThen, S1, S, Then).
% When DCG expansion throws an exception – remove offending term and rethrow.
user:term_expansion(throw_dcg_expansion_error(E), _) :-
throw(E).
user:term_expansion(Term0, Term) :-
nonvar(Term0),
dcg_rule(Term0, Term).
catch(dcg_rule(Term0, Term), E, Term = throw_dcg_expansion_error(E)).
%% seq(Seq)//
%