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C# AstGenerator.EnterRescueClause方法代码示例

本文整理汇总了C#中IronRuby.Compiler.Ast.AstGenerator.EnterRescueClause方法的典型用法代码示例。如果您正苦于以下问题:C# AstGenerator.EnterRescueClause方法的具体用法?C# AstGenerator.EnterRescueClause怎么用?C# AstGenerator.EnterRescueClause使用的例子?那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在IronRuby.Compiler.Ast.AstGenerator的用法示例。


在下文中一共展示了AstGenerator.EnterRescueClause方法的1个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的C#代码示例。

示例1: TransformExceptionHandling

        private MSA.Expression/*!*/ TransformExceptionHandling(AstGenerator/*!*/ gen, ResultOperation resultOperation) {
            Assert.NotNull(gen);

            MSA.Expression exceptionThrownVariable = gen.CurrentScope.DefineHiddenVariable("#exception-thrown", typeof(bool));
            MSA.ParameterExpression exceptionVariable = gen.CurrentScope.DefineHiddenVariable("#exception", typeof(Exception));
            MSA.Expression exceptionRethrowVariable = gen.CurrentScope.DefineHiddenVariable("#exception-rethrow", typeof(bool));
            MSA.Expression retryingVariable = gen.CurrentScope.DefineHiddenVariable("#retrying", typeof(bool));
            MSA.ParameterExpression evalUnwinder = gen.CurrentScope.DefineHiddenVariable("#unwinder", typeof(EvalUnwinder));
            MSA.Expression oldExceptionVariable = gen.CurrentScope.DefineHiddenVariable("#old-exception", typeof(Exception));

            MSA.Expression transformedBody;
            MSA.Expression transformedEnsure;
            MSA.Expression transformedElse;

            if (_ensureStatements != null) {
                transformedEnsure = Ast.Block(
                    // ensure:
                    Ast.Assign(oldExceptionVariable, Methods.GetCurrentException.OpCall(gen.CurrentScopeVariable)),
                    gen.TransformStatements(_ensureStatements, ResultOperation.Ignore),
                    Methods.SetCurrentException.OpCall(gen.CurrentScopeVariable, oldExceptionVariable),

                    // rethrow:
                    AstUtils.IfThen(
                        Ast.AndAlso(
                            exceptionRethrowVariable,
                            Ast.NotEqual(oldExceptionVariable, AstUtils.Constant(null))
                        ),
                        Ast.Throw(oldExceptionVariable)
                    ),
                    AstUtils.Empty()
                );
            } else {
                // rethrow:
                transformedEnsure = AstUtils.IfThen(
                    Ast.AndAlso(
                        exceptionRethrowVariable,
                        Ast.NotEqual(
                            Ast.Assign(oldExceptionVariable, Methods.GetCurrentException.OpCall(gen.CurrentScopeVariable)),
                            AstUtils.Constant(null, typeof(Exception)))
                        ),
                    Ast.Throw(oldExceptionVariable)
                );
            }

            if (_elseStatements != null) {
                transformedElse = gen.TransformStatements(_elseStatements, resultOperation);
            } else {
                transformedElse = AstUtils.Empty();
            }

            // body should do return, but else-clause is present => we cannot do return from the guarded statements: 
            // (the value of the last expression in the body cannot be the last executed expression statement => we can ignore it):
            transformedBody = gen.TransformStatements(_statements, (_elseStatements != null) ? ResultOperation.Ignore : resultOperation);

            MSA.Expression setInRescueFlag = null, clearInRescueFlag = null;
            var breakLabel = Ast.Label();
            var continueLabel = Ast.Label();

            // make rescue clause:
            MSA.Expression transformedRescue;
            if (_rescueClauses != null) {
                // outer-most EH blocks sets and clears runtime flag RuntimeFlowControl.InTryRescue:
                if (gen.CurrentRescue == null) {
                    setInRescueFlag = Ast.Assign(Ast.Field(gen.CurrentRfcVariable, RuntimeFlowControl.InRescueField), AstUtils.Constant(true));
                    clearInRescueFlag = Ast.Assign(Ast.Field(gen.CurrentRfcVariable, RuntimeFlowControl.InRescueField), AstUtils.Constant(false));
                } else {
                    setInRescueFlag = clearInRescueFlag = AstUtils.Empty();
                }

                gen.EnterRescueClause(retryingVariable, breakLabel, continueLabel);

                var handlers = new IfStatementTest[_rescueClauses.Count];
                for (int i = 0; i < handlers.Length; i++) {
                    handlers[i] = _rescueClauses[i].Transform(gen, resultOperation);
                }

                transformedRescue = Ast.Block(
                    setInRescueFlag,
                    AstUtils.Try(
                        AstUtils.If(handlers, Ast.Assign(exceptionRethrowVariable, AstUtils.Constant(true)))
                    ).Filter(evalUnwinder, Ast.Equal(Ast.Field(evalUnwinder, EvalUnwinder.ReasonField), AstUtils.Constant(BlockReturnReason.Retry)),
                        Ast.Block(
                            Ast.Assign(retryingVariable, AstUtils.Constant(true)),
                            Ast.Continue(continueLabel),
                            AstUtils.Empty()
                        )
                    )
                );

                gen.LeaveRescueClause();

            } else {
                transformedRescue = Ast.Assign(exceptionRethrowVariable, AstUtils.Constant(true));
            }

            if (_elseStatements != null) {
                transformedElse = AstUtils.Unless(exceptionThrownVariable, transformedElse);
            }

            var result = AstFactory.Infinite(breakLabel, continueLabel,
//.........这里部分代码省略.........
开发者ID:jcteague,项目名称:ironruby,代码行数:101,代码来源:Body.cs


注:本文中的IronRuby.Compiler.Ast.AstGenerator.EnterRescueClause方法示例由纯净天空整理自Github/MSDocs等开源代码及文档管理平台,相关代码片段筛选自各路编程大神贡献的开源项目,源码版权归原作者所有,传播和使用请参考对应项目的License;未经允许,请勿转载。