C# ConditionalBuilder.GetMetaObject方法代码示例

        private static DynamicMetaObject/*!*/ MakeBinaryOperatorResult(DynamicMetaObject/*!*/[]/*!*/ types, DynamicMetaObjectBinder/*!*/ operation, PythonOperationKind op, SlotOrFunction/*!*/ fCand, SlotOrFunction/*!*/ rCand, PythonTypeSlot fSlot, PythonTypeSlot rSlot, DynamicMetaObject errorSuggestion) {
            Assert.NotNull(operation, fCand, rCand);

            SlotOrFunction fTarget, rTarget;
            PythonContext state = PythonContext.GetPythonContext(operation);

            ConditionalBuilder bodyBuilder = new ConditionalBuilder(operation);

            if ((op & PythonOperationKind.InPlace) != 0) {
                // in place operator, see if there's a specific method that handles it.
                SlotOrFunction function = SlotOrFunction.GetSlotOrFunction(PythonContext.GetPythonContext(operation), Symbols.OperatorToSymbol(op), types);

                // we don't do a coerce for in place operators if the lhs implements __iop__
                if (!MakeOneCompareGeneric(function, false, types, MakeCompareReturn, bodyBuilder, typeof(object))) {
                    // the method handles it and always returns a useful value.
                    return bodyBuilder.GetMetaObject(types);
                }
            }

            if (!SlotOrFunction.GetCombinedTargets(fCand, rCand, out fTarget, out rTarget) &&
                fSlot == null &&
                rSlot == null &&
                !ShouldCoerce(state, op, types[0], types[1], false) &&
                !ShouldCoerce(state, op, types[1], types[0], false) &&
                bodyBuilder.NoConditions) {
                return MakeRuleForNoMatch(operation, op, errorSuggestion, types);
            }

            if (ShouldCoerce(state, op, types[0], types[1], false) &&
                (op != PythonOperationKind.Mod || !MetaPythonObject.GetPythonType(types[0]).IsSubclassOf(TypeCache.String))) {
                // need to try __coerce__ first.
                DoCoerce(state, bodyBuilder, op, types, false);
            }

            if (MakeOneTarget(PythonContext.GetPythonContext(operation), fTarget, fSlot, bodyBuilder, false, types)) {
                if (ShouldCoerce(state, op, types[1], types[0], false)) {
                    // need to try __coerce__ on the reverse first                    
                    DoCoerce(state, bodyBuilder, op, new DynamicMetaObject[] { types[1], types[0] }, true);
                }

                if (rSlot != null) {
                    MakeSlotCall(PythonContext.GetPythonContext(operation), types, bodyBuilder, rSlot, true);
                    bodyBuilder.FinishCondition(MakeBinaryThrow(operation, op, types).Expression, typeof(object));
                } else if (MakeOneTarget(PythonContext.GetPythonContext(operation), rTarget, rSlot, bodyBuilder, false, types)) {
                    // need to fallback to throwing or coercion
                    bodyBuilder.FinishCondition(MakeBinaryThrow(operation, op, types).Expression, typeof(object));
                }
            }

            return bodyBuilder.GetMetaObject(types);
        }

            public override DynamicMetaObject/*!*/ CompleteRuleTarget(DynamicMetaObjectBinder/*!*/ metaBinder, DynamicMetaObject/*!*/[]/*!*/ args, Func<DynamicMetaObject> customFailure) {
                ConditionalBuilder cb = new ConditionalBuilder();
                _slot.MakeGetExpression(
                    Binder,
                    AstUtils.Constant(PythonContext.SharedContext),
                    args[0],
                    new DynamicMetaObject(
                        Ast.Call(
                            typeof(DynamicHelpers).GetMethod("GetPythonType"),
                            AstUtils.Convert(args[0].Expression, typeof(object))
                        ),
                        BindingRestrictions.Empty,
                        DynamicHelpers.GetPythonType(args[0].Value)
                    ),
                    cb
                );
                if (!cb.IsFinal) {
                    cb.FinishCondition(metaBinder.Throw(Ast.New(typeof(InvalidOperationException))));
                }

                Expression callable = cb.GetMetaObject().Expression;
                Expression[] exprArgs = new Expression[args.Length - 1];
                for (int i = 1; i < args.Length; i++) {
                    exprArgs[i - 1] = args[i].Expression;
                }

                Expression retVal = DynamicExpression.Dynamic(
                    PythonContext.Invoke(
                        new CallSignature(exprArgs.Length)
                    ),
                    typeof(object),
                    ArrayUtils.Insert(AstUtils.Constant(PythonContext.SharedContext), (Expression)callable, exprArgs)
                );

                if (IsSetter) {
                    retVal = Ast.Block(retVal, args[args.Length - 1].Expression);
                }

                return new DynamicMetaObject(
                    retVal,
                    BindingRestrictions.Combine(args)
                );
            }

//.........这里部分代码省略.........
            SlotOrFunction cfunc, rcfunc, eqfunc, reqfunc, ltfunc, gtfunc, rltfunc, rgtfunc;

            PythonContext state = PythonContext.GetPythonContext(operation);
            cfunc = SlotOrFunction.GetSlotOrFunction(state, "__cmp__", types);
            rcfunc = SlotOrFunction.GetSlotOrFunction(state, "__cmp__", rTypes);
            eqfunc = SlotOrFunction.GetSlotOrFunction(state, "__eq__", types);
            reqfunc = SlotOrFunction.GetSlotOrFunction(state, "__eq__", rTypes);
            ltfunc = SlotOrFunction.GetSlotOrFunction(state, "__lt__", types);
            gtfunc = SlotOrFunction.GetSlotOrFunction(state, "__gt__", types);
            rltfunc = SlotOrFunction.GetSlotOrFunction(state, "__lt__", rTypes);
            rgtfunc = SlotOrFunction.GetSlotOrFunction(state, "__gt__", rTypes);

            // inspect forward and reverse versions so we can pick one or both.
            SlotOrFunction cTarget, rcTarget, eqTarget, reqTarget, ltTarget, rgtTarget, gtTarget, rltTarget;
            SlotOrFunction.GetCombinedTargets(cfunc, rcfunc, out cTarget, out rcTarget);
            SlotOrFunction.GetCombinedTargets(eqfunc, reqfunc, out eqTarget, out reqTarget);
            SlotOrFunction.GetCombinedTargets(ltfunc, rgtfunc, out ltTarget, out rgtTarget);
            SlotOrFunction.GetCombinedTargets(gtfunc, rltfunc, out gtTarget, out rltTarget);

            PythonType xType = MetaPythonObject.GetPythonType(types[0]);
            PythonType yType = MetaPythonObject.GetPythonType(types[1]);

            // now build the rule from the targets.
            // bail if we're comparing to null and the rhs can't do anything special...
            if (xType.IsNull) {
                if (yType.IsNull) {
                    return new DynamicMetaObject(
                        AstUtils.Constant(0),
                        BindingRestrictions.Combine(types)
                    );
                } else if (yType.UnderlyingSystemType.IsPrimitive() || yType.UnderlyingSystemType == typeof(BigInteger)) {
                    return new DynamicMetaObject(
                        AstUtils.Constant(-1),
                        BindingRestrictions.Combine(types)
                    );
                }
            }

            ConditionalBuilder bodyBuilder = new ConditionalBuilder(operation);

            bool tryRich = true, more = true;
            if (xType == yType && cTarget != SlotOrFunction.Empty) {
                // if the types are equal try __cmp__ first
                if (ShouldCoerce(state, op, types[0], types[1], true)) {
                    // need to try __coerce__ first.
                    DoCoerce(state, bodyBuilder, PythonOperationKind.Compare, types, false);
                }

                more = more && MakeOneCompareGeneric(cTarget, false, types, MakeCompareReverse, bodyBuilder, typeof(int));

                if (xType != TypeCache.OldInstance) {
                    // try __cmp__ backwards for new-style classes and don't fallback to
                    // rich comparisons if available
                    more = more && MakeOneCompareGeneric(rcTarget, true, types, MakeCompareReverse, bodyBuilder, typeof(int));
                    tryRich = false;
                }
            }

            if (tryRich && more) {
                // try the >, <, ==, !=, >=, <=.  These don't get short circuited using the more logic
                // because they don't give a definitive answer even if they return bool.  Only if they
                // return true do we know to return 0, -1, or 1.
                // try eq
                MakeOneCompareGeneric(eqTarget, false, types, MakeCompareToZero, bodyBuilder, typeof(int));
                MakeOneCompareGeneric(reqTarget, true, types, MakeCompareToZero, bodyBuilder, typeof(int));

                // try less than & reverse
                MakeOneCompareGeneric(ltTarget, false, types, MakeCompareToNegativeOne, bodyBuilder, typeof(int));
                MakeOneCompareGeneric(rgtTarget, true, types, MakeCompareToNegativeOne, bodyBuilder, typeof(int));

                // try greater than & reverse
                MakeOneCompareGeneric(gtTarget, false, types, MakeCompareToOne, bodyBuilder, typeof(int));
                MakeOneCompareGeneric(rltTarget, true, types, MakeCompareToOne, bodyBuilder, typeof(int));
            }

            if (xType != yType) {
                if (more && ShouldCoerce(state, op, types[0], types[1], true)) {
                    // need to try __coerce__ first.
                    DoCoerce(state, bodyBuilder, PythonOperationKind.Compare, types, false);
                }

                more = more && MakeOneCompareGeneric(cTarget, false, types, MakeCompareReverse, bodyBuilder, typeof(int));

                if (more && ShouldCoerce(state, op, types[1], types[0], true)) {
                    // try __coerce__ first
                    DoCoerce(state, bodyBuilder, PythonOperationKind.Compare, rTypes, true, delegate(Expression e) {
                        return ReverseCompareValue(e);
                    });
                }

                more = more && MakeOneCompareGeneric(rcTarget, true, types, MakeCompareReverse, bodyBuilder, typeof(int));
            }

            if (more) {
                // fall back to compare types
                bodyBuilder.FinishCondition(MakeFallbackCompare(operation, op, types), typeof(int));
            }

            return bodyBuilder.GetMetaObject(types);
        }

        private static DynamicMetaObject/*!*/ MakeComparisonOperation(DynamicMetaObject/*!*/[]/*!*/ types, DynamicMetaObjectBinder/*!*/ operation, PythonOperationKind opString, DynamicMetaObject errorSuggestion) {
            RestrictTypes(types);

            PythonOperationKind op = NormalizeOperator(opString);

            PythonContext state = PythonContext.GetPythonContext(operation);
            Debug.Assert(types.Length == 2);
            DynamicMetaObject xType = types[0], yType = types[1];
            string opSym = Symbols.OperatorToSymbol(op);
            string ropSym = Symbols.OperatorToReversedSymbol(op);
            // reverse
            DynamicMetaObject[] rTypes = new DynamicMetaObject[] { types[1], types[0] };

            SlotOrFunction fop, rop, cmp, rcmp;
            fop = SlotOrFunction.GetSlotOrFunction(state, opSym, types);
            rop = SlotOrFunction.GetSlotOrFunction(state, ropSym, rTypes);
            cmp = SlotOrFunction.GetSlotOrFunction(state, "__cmp__", types);
            rcmp = SlotOrFunction.GetSlotOrFunction(state, "__cmp__", rTypes);

            ConditionalBuilder bodyBuilder = new ConditionalBuilder(operation);

            SlotOrFunction.GetCombinedTargets(fop, rop, out fop, out rop);
            SlotOrFunction.GetCombinedTargets(cmp, rcmp, out cmp, out rcmp);

            bool shouldWarn = false;
            WarningInfo info = null;

            // first try __op__ or __rop__ and return the value
            shouldWarn = fop.ShouldWarn(state, out info);
            if (MakeOneCompareGeneric(fop, false, types, MakeCompareReturn, bodyBuilder, typeof(object))) {
                shouldWarn = shouldWarn || rop.ShouldWarn(state, out info);
                if (MakeOneCompareGeneric(rop, true, types, MakeCompareReturn, bodyBuilder, typeof(object))) {

                    // then try __cmp__ or __rcmp__ and compare the resulting int appropriaetly
                    shouldWarn = shouldWarn || cmp.ShouldWarn(state, out info);

                    if (ShouldCoerce(state, opString, xType, yType, true)) {
                        DoCoerce(state, bodyBuilder, PythonOperationKind.Compare, types, false, delegate(Expression e) {
                            return GetCompareTest(op, e, false);
                        });
                    }

                    if (MakeOneCompareGeneric(
                        cmp,
                        false,
                        types,
                        delegate(ConditionalBuilder builder, Expression retCond, Expression expr, bool reverse, Type retType) {
                            MakeCompareTest(op, builder, retCond, expr, reverse, retType);
                        },
                        bodyBuilder,
                        typeof(object))) {

                        shouldWarn = shouldWarn || rcmp.ShouldWarn(state, out info);

                        if (ShouldCoerce(state, opString, yType, xType, true)) {
                            DoCoerce(state, bodyBuilder, PythonOperationKind.Compare, rTypes, true, delegate(Expression e) {
                                return GetCompareTest(op, e, true);
                            });
                        }

                        if (MakeOneCompareGeneric(
                            rcmp,
                            true,
                            types,
                            delegate(ConditionalBuilder builder, Expression retCond, Expression expr, bool reverse, Type retType) {
                                MakeCompareTest(op, builder, retCond, expr, reverse, retType);
                            },
                            bodyBuilder,
                            typeof(object))) {
                            if (errorSuggestion != null) {
                                bodyBuilder.FinishCondition(errorSuggestion.Expression, typeof(object));
                            } else {
                                bodyBuilder.FinishCondition(BindingHelpers.AddPythonBoxing(MakeFallbackCompare(operation, op, types)), typeof(object));
                            }
                        }
                    }
                }
            }

            DynamicMetaObject res = bodyBuilder.GetMetaObject(types);
            if (!shouldWarn || res == null) {
                return res;
            } else {
                return info.AddWarning(Ast.Constant(state.SharedContext), res);
            }
        }

        internal static DynamicMetaObject Call(DynamicMetaObjectBinder/*!*/ call, DynamicMetaObject target, DynamicMetaObject/*!*/[]/*!*/ args) {
            Assert.NotNull(call, args);
            Assert.NotNullItems(args);

            if (target.NeedsDeferral()) {
                return call.Defer(ArrayUtils.Insert(target, args));
            }

            foreach (DynamicMetaObject mo in args) {
                if (mo.NeedsDeferral()) {
                    RestrictTypes(args);

                    return call.Defer(
                        ArrayUtils.Insert(target, args)
                    );
                }
            }

            DynamicMetaObject self = target.Restrict(target.GetLimitType());

            ValidationInfo valInfo = BindingHelpers.GetValidationInfo(target);
            PythonType pt = DynamicHelpers.GetPythonType(target.Value);
            BinderState state = BinderState.GetBinderState(call);

            // look for __call__, if it's present dispatch to it.  Otherwise fall back to the
            // default binder
            PythonTypeSlot callSlot;
            if (!typeof(Delegate).IsAssignableFrom(target.GetLimitType()) &&
                pt.TryResolveSlot(state.Context, Symbols.Call, out callSlot)) {
                ConditionalBuilder cb = new ConditionalBuilder(call);
                Expression body;

                callSlot.MakeGetExpression(
                    state.Binder,
                    BinderState.GetCodeContext(call),
                    self.Expression,
                    GetPythonType(self),
                    cb
                );
                
                if (!cb.IsFinal) {
                    cb.FinishCondition(GetCallError(self));
                }

                Expression[] callArgs = ArrayUtils.Insert(
                    BinderState.GetCodeContext(call),
                    cb.GetMetaObject().Expression, 
                    DynamicUtils.GetExpressions(args)
                );

                body = Ast.Dynamic(
                    BinderState.GetBinderState(call).Invoke(
                        BindingHelpers.GetCallSignature(call)
                    ),
                    typeof(object),
                    callArgs
                );

                return BindingHelpers.AddDynamicTestAndDefer(
                    call,
                    new DynamicMetaObject(body, self.Restrictions.Merge(BindingRestrictions.Combine(args))),
                    args,
                    valInfo
                );
            }

            return null;
        }

        private static DynamicMetaObject/*!*/ MakeComparisonOperation(DynamicMetaObject/*!*/[]/*!*/ types, DynamicMetaObjectBinder/*!*/ operation, PythonOperationKind opString) {
            RestrictTypes(types);

            PythonOperationKind op = NormalizeOperator(opString);

            BinderState state = BinderState.GetBinderState(operation);
            Debug.Assert(types.Length == 2);
            DynamicMetaObject xType = types[0], yType = types[1];
            SymbolId opSym = Symbols.OperatorToSymbol(op);
            SymbolId ropSym = Symbols.OperatorToReversedSymbol(op);
            // reverse
            DynamicMetaObject[] rTypes = new DynamicMetaObject[] { types[1], types[0] };

            SlotOrFunction fop, rop, cmp, rcmp;
            fop = SlotOrFunction.GetSlotOrFunction(state, opSym, types);
            rop = SlotOrFunction.GetSlotOrFunction(state, ropSym, rTypes);
            cmp = SlotOrFunction.GetSlotOrFunction(state, Symbols.Cmp, types);
            rcmp = SlotOrFunction.GetSlotOrFunction(state, Symbols.Cmp, rTypes);

            ConditionalBuilder bodyBuilder = new ConditionalBuilder(operation);

            SlotOrFunction.GetCombinedTargets(fop, rop, out fop, out rop);
            SlotOrFunction.GetCombinedTargets(cmp, rcmp, out cmp, out rcmp);

            // first try __op__ or __rop__ and return the value
            if (MakeOneCompareGeneric(fop, false, types, MakeCompareReturn, bodyBuilder)) {
                if (MakeOneCompareGeneric(rop, true, types, MakeCompareReturn, bodyBuilder)) {

                    // then try __cmp__ or __rcmp__ and compare the resulting int appropriaetly
                    if (ShouldCoerce(state, opString, xType, yType, true)) {
                        DoCoerce(state, bodyBuilder, PythonOperationKind.Compare, types, false, delegate(Expression e) {
                            return GetCompareTest(op, e, false);
                        });
                    }

                    if (MakeOneCompareGeneric(
                        cmp,
                        false,
                        types,
                        delegate(ConditionalBuilder builder, Expression retCond, Expression expr, bool reverse) {
                            MakeCompareTest(op, builder, retCond, expr, reverse);
                        },
                        bodyBuilder)) {

                        if (ShouldCoerce(state, opString, yType, xType, true)) {
                            DoCoerce(state, bodyBuilder, PythonOperationKind.Compare, rTypes, true, delegate(Expression e) {
                                return GetCompareTest(op, e, true);
                            });
                        }

                        if (MakeOneCompareGeneric(
                            rcmp,
                            true,
                            types,
                            delegate(ConditionalBuilder builder, Expression retCond, Expression expr, bool reverse) {
                                MakeCompareTest(op, builder, retCond, expr, reverse);
                            },
                            bodyBuilder)) {
                            bodyBuilder.FinishCondition(MakeFallbackCompare(op, types));
                        }
                    }
                }
            }

            return bodyBuilder.GetMetaObject(types);
        }