Antlr4.Codegen.Model.SemPred.SemPred C# (CSharp) Method

        public SemPred(OutputModelFactory factory, [NotNull] ActionAST ast)
            : base(factory, ast)
        {

            Debug.Assert(ast.atnState != null
                && ast.atnState.NumberOfTransitions == 1
                && ast.atnState.Transition(0) is AbstractPredicateTransition);

            GrammarAST failNode = ast.GetOptionAST("fail");
            predicate = ast.Text;
            if (predicate.StartsWith("{") && predicate.EndsWith("}?"))
            {
                predicate = predicate.Substring(1, predicate.Length - 3);
            }
            predicate = factory.GetTarget().GetTargetStringLiteralFromString(predicate);

            if (failNode == null)
                return;

            if (failNode is ActionAST)
            {
                ActionAST failActionNode = (ActionAST)failNode;
                RuleFunction rf = factory.GetCurrentRuleFunction();
                failChunks = ActionTranslator.TranslateAction(factory, rf,
                                                              failActionNode.Token,
                                                              failActionNode);
            }
            else
            {
                msg = factory.GetTarget().GetTargetStringLiteralFromANTLRStringLiteral(factory.GetGenerator(),
                                                                              failNode.Text,
                                                                              true);
            }
        }
    }