23MessageID.IDS_FeatureAnonymousTypes.CheckFeatureAvailability(diagnostics, node.NewKeyword);

546CheckFeatureAvailability(namedArgument, MessageID.IDS_FeatureInitOnlySetters, diagnostics);

22MessageID.IDS_FeatureAsync.CheckFeatureAvailability(diagnostics, node.AwaitKeyword); 240!CheckFeatureAvailability(awaitNodeOrToken, MessageID.IDS_FeatureUnsafeEvolution, diagnostics)) 245(nodeOrToken.SyntaxTree as CSharpSyntaxTree)?.Options?.IsFeatureEnabled(MessageID.IDS_AwaitInCatchAndFinally) == false) 251(nodeOrToken.SyntaxTree as CSharpSyntaxTree)?.Options?.IsFeatureEnabled(MessageID.IDS_AwaitInCatchAndFinally) == false)

217CheckFeatureAvailability(syntax, MessageID.IDS_FeatureDefaultTypeParameterConstraint, diagnostics); 320CheckFeatureAvailability(allowsConstraint, MessageID.IDS_FeatureAllowsRefStructConstraint, diagnostics); 567CheckFeatureAvailability(syntax, MessageID.IDS_FeatureEnumGenericTypeConstraint, diagnostics); 572CheckFeatureAvailability(syntax, MessageID.IDS_FeatureDelegateGenericTypeConstraint, diagnostics);

486CheckFeatureAvailability(syntax, MessageID.IDS_FeatureStaticAbstractMembersInInterfaces, diagnostics); 498CheckFeatureAvailability(syntax, MessageID.IDS_FeatureCheckedUserDefinedOperators, diagnostics); 504CheckFeatureAvailability(syntax, MessageID.IDS_FeatureUnions, diagnostics); 521CheckFeatureAvailability(syntax, MessageID.IDS_FeatureInlineArrays, diagnostics); 565CheckFeatureAvailability(syntax, MessageID.IDS_FeatureFirstClassSpan, diagnostics); 2473if (targetTyped && !destination.IsErrorType() && !Compilation.IsFeatureEnabled(MessageID.IDS_FeatureTargetTypedConditional)) 2481new CSharpRequiredLanguageVersion(MessageID.IDS_FeatureTargetTypedConditional.RequiredVersion())); 2843Debug.Assert(syntax.IsFeatureEnabled(MessageID.IDS_FeatureInferredDelegateType)); 3063Error(diagnostics, ErrorCode.WRN_OptionalParamValueMismatch, lambdaParameter.GetFirstLocation(), p + 1, lambdaParamDefault, delegateParamDefault ?? ((object)MessageID.IDS_Missing.Localize())); 3109CheckFeatureAvailability(syntax, MessageID.IDS_FeatureRefStructs, diagnostics); 3422else if (WasImplicitReceiver(receiverOpt) && !(IsInsideNameof && Compilation.IsFeatureEnabled(MessageID.IDS_FeatureInstanceMemberInNameof)))

233CheckFeatureAvailability(syntax, MessageID.IDS_FeatureExtensions, diagnostics); 241CheckFeatureAvailability(syntax, MessageID.IDS_FeatureExtensions, diagnostics); 247CheckFeatureAvailability(syntax, MessageID.IDS_FeatureExtensionIndexers, diagnostics); 576CheckFeatureAvailability(syntax, MessageID.IDS_FeatureNativeInt, diagnostics); 1145CheckFeatureAvailability(parameter.ReadOnlyKeyword, MessageID.IDS_FeatureRefReadonlyParameters, diagnostics, forceWarning: true);

45MessageID.IDS_FeatureMixedDeclarationsAndExpressionsInDeconstruction 54MessageID.IDS_FeatureMixedDeclarationsAndExpressionsInDeconstruction 768MessageID.IDS_FeatureTuples.CheckFeatureAvailability(diagnostics, component.Designation); 776MessageID.IDS_FeatureTuples.CheckFeatureAvailability(diagnostics, node);

38if (!isExplicit && IsInsideNameof && Compilation.IsFeatureEnabled(MessageID.IDS_FeatureInstanceMemberInNameof)) 457if (CheckFeatureAvailability(syntax, MessageID.IDS_FeatureInferredDelegateType, diagnostics)) 753MessageID.IDS_FeatureDefaultLiteral.CheckFeatureAvailability(diagnostics, node); 916MessageID.IDS_FeatureThrowExpression.CheckFeatureAvailability(diagnostics, node.ThrowKeyword); 1039MessageID.IDS_FeatureTuples.CheckFeatureAvailability(diagnostics, node); 1572var requiredVersion = MessageID.IDS_FeatureFieldKeyword.RequiredVersion(); 1614case ManagedKind.UnmanagedWithGenerics when MessageID.IDS_FeatureUnmanagedConstructedTypes.GetFeatureAvailabilityDiagnosticInfo(compilation) is CSDiagnosticInfo diagnosticInfo: 1632MessageID.IDS_FeatureDefault.CheckFeatureAvailability(diagnostics, node.Keyword); 1933CheckFeatureAvailability(node, MessageID.IDS_FeatureDiscards, diagnostics); 2389if (!IsInsideNameof || (EnclosingNameofArgument != node && !node.IsFeatureEnabled(MessageID.IDS_FeatureInstanceMemberInNameof))) 2423CheckFeatureAvailability(node, MessageID.IDS_FeatureInstanceMemberInNameof, diagnostics); 2683CheckFeatureAvailability(node, MessageID.IDS_FeatureIndexOperator, diagnostics); 2724CheckFeatureAvailability(node, MessageID.IDS_FeatureRangeOperator, diagnostics); 2905diagnostics.Add(ErrorCode.ERR_NoExplicitConv, syntax.Location, MessageID.IDS_SK_METHOD.Localize(), targetType); 3079nameString = MessageID.IDS_Lambda.Localize().ToString(); 3214MessageID.IDS_FeatureReadOnlyReferences.CheckFeatureAvailability(diagnostics, argumentSyntax.RefKindKeyword); 3219MessageID.IDS_FeatureOutVar.CheckFeatureAvailability(diagnostics, argumentSyntax.RefKindKeyword); 3299CheckFeatureAvailability(declarationExpression, MessageID.IDS_FeatureExpressionVariablesInQueriesAndInitializers, diagnostics); 3377CheckFeatureAvailability(syntax, MessageID.IDS_FeatureRefUnsafeInIteratorAsync, diagnostics); 3417CheckFeatureAvailability(nameColonSyntax, MessageID.IDS_FeatureNamedArgument, diagnostics); 3464new CSharpRequiredLanguageVersion(MessageID.IDS_FeatureNonTrailingNamedArguments.RequiredVersion())); 3988if (!Compilation.IsFeatureEnabled(MessageID.IDS_FeatureRefReadonlyParameters)) 3994var available = CheckFeatureAvailability(argument.Syntax, MessageID.IDS_FeatureRefReadonlyParameters, diagnostics); 4206MessageID.IDS_FeatureImplicitArray.CheckFeatureAvailability(diagnostics, node.NewKeyword); 4671LanguageVersion requiredVersion = MessageID.IDS_FeatureNestedStackalloc.RequiredVersion(); 4677MessageID.IDS_FeatureNestedStackalloc.CheckFeatureAvailability(diagnostics, node.GetFirstToken()); 4708CheckFeatureAvailability(node, MessageID.IDS_FeatureRefStructs, diagnostics); 4771MessageID.IDS_FeatureStackAllocInitializer.CheckFeatureAvailability(diagnostics, stackAllocKeyword); 5274MessageID.IDS_FeatureImplicitObjectCreation.CheckFeatureAvailability(diagnostics, node.NewKeyword); 5359MessageID.IDS_FeatureCollectionExpressions.CheckFeatureAvailability(diagnostics, syntax, syntax.OpenBracketToken.GetLocation()); 5368MessageID.IDS_FeatureCollectionExpressionArguments.CheckFeatureAvailability(diagnostics, syntax, withElementSyntax.WithKeyword.GetLocation()); 5865MessageID.IDS_FeatureObjectInitializer.CheckFeatureAvailability(diagnostics, initializerSyntax.OpenBraceToken); 6049MessageID.IDS_FeatureDictionaryInitializer.CheckFeatureAvailability(diagnostics, implicitIndexing.ArgumentList.OpenBracketToken); 6146MessageID.IDS_FeatureImplicitIndexerInitializer.CheckFeatureAvailability(diagnostics, implicitIndexer.Syntax); 6419MessageID.IDS_FeatureCollectionInitializer.CheckFeatureAvailability(diagnostics, initializerSyntax.OpenBraceToken); 6479CheckFeatureAvailability(node, MessageID.IDS_FeatureRefStructInterfaces, diagnostics); 7589MessageID.IDS_FeatureRawStringLiterals.CheckFeatureAvailability(diagnostics, node); 7602CheckFeatureAvailability(node, MessageID.IDS_FeatureRawStringLiterals, diagnostics); 7605CheckFeatureAvailability(node, MessageID.IDS_FeatureUtf8StringLiterals, diagnostics); 7628CheckFeatureAvailability(node.Keyword, MessageID.IDS_FeatureUnsafeEvolution, diagnostics); 7950var msgId = ((UnboundLambda)boundLeft).MessageID; 8151CheckFeatureAvailability(boundLeft.Syntax, MessageID.IDS_FeatureStaticAbstractMembersInInterfaces, diagnostics); 8198Compilation.LanguageVersion < MessageID.IDS_FeatureNullableReferenceTypes.RequiredVersion()) 8228Error(diagnostics, ErrorCode.ERR_BadSKunknown, methodGroup.NameSyntax, method, MessageID.IDS_SK_METHOD.Localize()); 8288MessageID.IDS_FeatureExtensions.CheckFeatureAvailability(diagnostics, syntax); 9852CheckFeatureAvailability(node, MessageID.IDS_FeatureIndexingMovableFixedBuffers, diagnostics); 9898CheckFeatureAvailability(node, MessageID.IDS_FeatureRefFields, diagnostics); 10142else if (CheckFeatureAvailability(node, MessageID.IDS_FeatureInstanceMemberInNameof, diagnostics)) 10520CheckFeatureAvailability(node, MessageID.IDS_FeatureInlineArrays, diagnostics); 11321_ = MessageID.IDS_FeatureIndexOperator.CheckFeatureAvailability(diagnostics, syntax); 12339MessageID.IDS_FeatureNullPropagatingOperator.CheckFeatureAvailability(diagnostics, node.OperatorToken); 12347MessageID.IDS_FeatureNullConditionalAssignment.CheckFeatureAvailability(diagnostics, assignment.OperatorToken); 12528var msgId = ((UnboundLambda)receiver).MessageID;

119return isIteratorBody && compilation.IsFeatureEnabled(MessageID.IDS_FeatureRefUnsafeInIteratorAsync);

21if (CheckFeatureAvailability(node, MessageID.IDS_FeatureInterpolatedStrings, diagnostics)) 27CheckFeatureAvailability(node, MessageID.IDS_FeatureRawStringLiterals, diagnostics); 32if (startText.StartsWith("@$\"") && !Compilation.IsFeatureEnabled(MessageID.IDS_FeatureAltInterpolatedVerbatimStrings)) 37new CSharpRequiredLanguageVersion(MessageID.IDS_FeatureAltInterpolatedVerbatimStrings.RequiredVersion())); 53var newLinesInInterpolationsAllowed = this.Compilation.IsFeatureEnabled(MessageID.IDS_FeatureNewLinesInInterpolations); 86new CSharpRequiredLanguageVersion(MessageID.IDS_FeatureNewLinesInInterpolations.RequiredVersion())); 662CheckFeatureAvailability(syntax, MessageID.IDS_FeatureImprovedInterpolatedStrings, diagnostics); 664else if (!Compilation.IsFeatureEnabled(MessageID.IDS_FeatureImprovedInterpolatedStrings) && diagnostics.AccumulatesDiagnostics) 689CheckFeatureAvailability(value.Syntax, MessageID.IDS_FeatureImprovedInterpolatedStrings, diagnostics); 699CheckFeatureAvailability(value.Syntax, MessageID.IDS_FeatureImprovedInterpolatedStrings, diagnostics);

161MessageID msgId; 164msgId = MessageID.IDS_SK_FIELD; 168msgId = MessageID.IDS_SK_PROPERTY; 176MessageID.IDS_SK_METHOD.Localize()); 1310CheckFeatureAvailability(receiverArgument.Syntax, MessageID.IDS_FeatureRefExtensionMethods, diagnostics); 1316CheckFeatureAvailability(receiverArgument.Syntax, MessageID.IDS_FeatureRefExtensionMethods, diagnostics); 1882MessageID.IDS_FeatureParamsCollections.CheckFeatureAvailability(diagnostics, node); 2403CheckFeatureAvailability(node, MessageID.IDS_FeatureNameof, diagnostics);

63MessageID.IDS_FeatureLambda.CheckFeatureAvailability(diagnostics, lambdaSyntax.ArrowToken); 95MessageID.IDS_FeatureAnonDelegates.CheckFeatureAvailability(diagnostics, anon.DelegateKeyword); 113MessageID.IDS_FeatureAsync.CheckFeatureAvailability(diagnostics, modifier); 118MessageID.IDS_FeatureStaticAnonymousFunction.CheckFeatureAvailability(diagnostics, modifier); 170MessageID.IDS_FeatureLambdaOptionalParameters.CheckFeatureAvailability(diagnostics, p.Default.EqualsToken); 281MessageID.IDS_FeatureLambdaAttributes.CheckFeatureAvailability(diagnostics, attributeList); 294MessageID.IDS_FeatureLambdaReturnType.CheckFeatureAvailability(diagnostics, syntax); 358CheckFeatureAvailability(parameter, MessageID.IDS_FeatureSimpleLambdaParameterModifiers, diagnostics); 381bool allowShadowingNames = binder.Compilation.IsFeatureEnabled(MessageID.IDS_FeatureNameShadowingInNestedFunctions); 399MessageID.IDS_FeatureLambdaDiscardParameters.CheckFeatureAvailability(

1886diagInfo = diagnose ? new CSDiagnosticInfo(ErrorCode.ERR_HasNoTypeVars, namedType, MessageID.IDS_SK_TYPE.Localize()) : null; 1891diagInfo = diagnose ? new CSDiagnosticInfo(ErrorCode.ERR_BadArity, namedType, MessageID.IDS_SK_TYPE.Localize(), namedType.Arity) : null; 1907diagInfo = diagnose ? new CSDiagnosticInfo(ErrorCode.ERR_HasNoTypeVars, method, MessageID.IDS_SK_METHOD.Localize()) : null; 1912diagInfo = diagnose ? new CSDiagnosticInfo(ErrorCode.ERR_BadArity, method, MessageID.IDS_SK_METHOD.Localize(), method.Arity) : null;

121bool allowShadowing = Compilation.IsFeatureEnabled(MessageID.IDS_FeatureNameShadowingInNestedFunctions);

348!node.IsFeatureEnabled(MessageID.IDS_FeatureUserDefinedCompoundAssignmentOperators)) 495CheckFeatureAvailability(node, MessageID.IDS_FeatureExtensions, diagnostics); 979CheckFeatureAvailability(node, MessageID.IDS_FeatureTupleEquality, diagnostics); 2226Binder.CheckFeatureAvailability(node, MessageID.IDS_DefaultInterfaceImplementation, diagnostics); 3461!node.IsFeatureEnabled(MessageID.IDS_FeatureUserDefinedCompoundAssignmentOperators)) 3601CheckFeatureAvailability(node, MessageID.IDS_FeatureExtensions, diagnostics); 4008result = CheckFeatureAvailability(node, MessageID.IDS_FeatureStaticAbstractMembersInInterfaces, diagnostics); 4019result = CheckFeatureAvailability(node, MessageID.IDS_FeatureStaticAbstractMembersInInterfaces, diagnostics); 4027result &= CheckFeatureAvailability(node, MessageID.IDS_FeatureUnsignedRightShift, diagnostics); 4038result &= CheckFeatureAvailability(node, MessageID.IDS_FeatureExtensions, diagnostics); 4042result &= CheckFeatureAvailability(node, MessageID.IDS_FeatureCheckedUserDefinedOperators, diagnostics); 4046result &= CheckFeatureAvailability(node, MessageID.IDS_FeatureUnsignedRightShift, diagnostics); 4057MessageID.IDS_FeatureNullableReferenceTypes.CheckFeatureAvailability(diagnostics, node.OperatorToken); 4832((CSharpParseOptions)node.SyntaxTree.Options).IsFeatureEnabled(MessageID.IDS_FeaturePatternMatching)) 4850if (((CSharpParseOptions)node.SyntaxTree.Options).IsFeatureEnabled(MessageID.IDS_FeaturePatternMatching) && 4881if (wasUnderscore && ((CSharpParseOptions)node.SyntaxTree.Options).IsFeatureEnabled(MessageID.IDS_FeatureRecursivePatterns)) 5708CheckFeatureAvailability(node, MessageID.IDS_FeatureUnconstrainedTypeParameterInNullCoalescingOperator, diagnostics); 5846MessageID.IDS_FeatureCoalesceAssignmentExpression.CheckFeatureAvailability(diagnostics, node.OperatorToken); 5965CheckFeatureAvailability(node, MessageID.IDS_FeatureRefConditional, diagnostics); 6118CheckFeatureAvailability(syntax, MessageID.IDS_FeatureNativeInt, diagnostics); 6134CheckFeatureAvailability(syntax, MessageID.IDS_FeatureNativeInt, diagnostics);

34MessageID.IDS_FeatureUnions.CheckFeatureAvailability(diagnostics, node); 63MessageID.IDS_FeaturePatternMatching.CheckFeatureAvailability(diagnostics, node.IsKeyword); 204MessageID.IDS_FeatureRecursivePatterns.CheckFeatureAvailability(diagnostics, node.SwitchKeyword); 259MessageID.IDS_FeatureParenthesizedPattern.CheckFeatureAvailability(diagnostics, node.OpenParenToken); 369CheckFeatureAvailability(node, MessageID.IDS_FeatureListPattern, diagnostics); 475MessageID.IDS_FeatureRecursivePatterns.CheckFeatureAvailability(diagnostics, node); 666CheckFeatureAvailability(patternExpression, MessageID.IDS_FeatureNullPointerConstantPattern, diagnostics); 723var requiredVersion = MessageID.IDS_FeatureRecursivePatterns.RequiredVersion(); 747if (MessageID.IDS_FeatureSpanCharConstantPattern.CheckFeatureAvailability(diagnostics, Compilation, node.Location)) 933LanguageVersion requiredVersion = MessageID.IDS_FeatureGenericPatternMatching.RequiredVersion(); 1091CheckFeatureAvailability(designation, MessageID.IDS_FeatureExpressionVariablesInQueriesAndInitializers, diagnostics); 1148MessageID.IDS_FeatureRecursivePatterns.CheckFeatureAvailability(diagnostics, node); 1316MessageID.IDS_FeatureExtendedPropertyPatterns.CheckFeatureAvailability(diagnostics, subPattern.ExpressionColon.ColonToken); 1463if (Compilation.LanguageVersion < MessageID.IDS_FeatureRecursivePatterns.RequiredVersion()) 1546|| (inputType.IsPointerType() && Compilation.LanguageVersion < MessageID.IDS_FeatureRecursivePatterns.RequiredVersion())) 1606MessageID.IDS_FeatureRecursivePatterns.CheckFeatureAvailability(diagnostics, node); 1724MessageID.IDS_FeatureExtendedPropertyPatterns.CheckFeatureAvailability(diagnostics, p.ExpressionColon.ColonToken); 1764MessageID.IDS_FeatureUnions.CheckFeatureAvailability(diagnostics, expr is MemberAccessExpressionSyntax memberAccess ? memberAccess.Name : expr); // Since new exhaustiveness rules will be used by DecisionDagBuilder. 1941MessageID.IDS_FeatureTypePattern.CheckFeatureAvailability(diagnostics, node); 1972MessageID.IDS_FeatureRelationalPattern.CheckFeatureAvailability(diagnostics, node.OperatorToken); 2080MessageID.IDS_FeatureNotPattern.CheckFeatureAvailability(diagnostics, node.OperatorToken); 2156MessageID.IDS_FeatureOrPattern.CheckFeatureAvailability(diagnostics, node.OperatorToken); 2177MessageID.IDS_FeatureAndPattern.CheckFeatureAvailability(diagnostics, node.OperatorToken);

26MessageID.IDS_FeatureQueryExpression.CheckFeatureAvailability(diagnostics, node.FromClause.FromKeyword); 778CheckFeatureAvailability(expression, MessageID.IDS_FeatureExpressionVariablesInQueriesAndInitializers, diagnostics, locals[0].GetFirstLocation()); 956diagnostics.Add(ErrorCode.ERR_BadSKunknown, ultimateReceiver.Syntax.Location, ((BoundNamespaceExpression)ultimateReceiver).NamespaceSymbol, MessageID.IDS_SK_NAMESPACE.Localize()); 961diagnostics.Add(ErrorCode.ERR_QueryNoProvider, node.Location, MessageID.IDS_AnonMethod.Localize(), methodName); 971Error(diagnostics, ErrorCode.ERR_BadSKunknown, ultimateReceiver.Syntax, ultimateReceiver.Type, MessageID.IDS_SK_TYVAR.Localize());

49CheckFeatureAvailability(attributeList, MessageID.IDS_FeatureLocalFunctionAttributes, diagnostics); 180CheckFeatureAvailability(node.UnsafeKeyword, MessageID.IDS_FeatureRefUnsafeInIteratorAsync, diagnostics); 217MessageID.IDS_FeatureIterators.CheckFeatureAvailability(diagnostics, statement.YieldKeyword); 222MessageID.IDS_FeatureAsyncStreams.CheckFeatureAvailability( 270else if (InUnsafeRegion && Compilation.IsFeatureEnabled(MessageID.IDS_FeatureRefUnsafeInIteratorAsync)) 396if (Compilation.LanguageVersion < MessageID.IDS_FeatureSwitchExpression.RequiredVersion()) 556MessageID.IDS_FeatureLocalFunctions.CheckFeatureAvailability(diagnostics, node.Identifier); 603MessageID.IDS_FeatureStaticLocalFunctions.CheckFeatureAvailability(diagnostics, modifier); 605MessageID.IDS_FeatureExternLocalFunctions.CheckFeatureAvailability(diagnostics, modifier); 1173return !CheckFeatureAvailability(identifierToken, MessageID.IDS_FeatureRefUnsafeInIteratorAsync, diagnostics); 1294bool extensibleFixedEnabled = ((CSharpParseOptions)initializerOpt.SyntaxTree.Options)?.IsFeatureEnabled(MessageID.IDS_FeatureExtensibleFixedStatement) != false; 1305CheckFeatureAvailability(initializerOpt.Syntax, MessageID.IDS_FeatureExtensibleFixedStatement, diagnostics); 1426MessageID.IDS_FeatureRefReassignment.CheckFeatureAvailability(diagnostics, node.Right.GetFirstToken()); 1642return MessageID.IDS_ArrayAccess.Localize(); 1646return MessageID.IDS_PointerElementAccess.Localize(); 2535syntax.IsFeatureEnabled(MessageID.IDS_FeatureInferredDelegateType)) 2966MessageID.IDS_FeatureLabeledBreakContinue.CheckFeatureAvailability(diagnostics, node, name.GetLocation()); 3443MessageID.IDS_FeatureExceptionFilter.CheckFeatureAvailability(diagnostics, filter.WhenKeyword); 3641ConstructorDeclarationSyntax or DestructorDeclarationSyntax => MessageID.IDS_FeatureExpressionBodiedDeOrConstructor, 3642AccessorDeclarationSyntax => MessageID.IDS_FeatureExpressionBodiedAccessor, 3643BaseMethodDeclarationSyntax => MessageID.IDS_FeatureExpressionBodiedMethod, 3644IndexerDeclarationSyntax => MessageID.IDS_FeatureExpressionBodiedIndexer, 3645PropertyDeclarationSyntax => MessageID.IDS_FeatureExpressionBodiedProperty, 3649LocalFunctionStatementSyntax => (MessageID?)null, 3756MessageID.IDS_TopLevelStatements.CheckFeatureAvailability(diagnostics, topLevelStatement);

117CheckFeatureAvailability(syntax, MessageID.IDS_FeatureImplicitLocal, diagnostics); 161CheckFeatureAvailability(syntax, MessageID.IDS_FeatureUnmanagedGenericTypeConstraint, diagnostics); 164CheckFeatureAvailability(identifierSyntax, MessageID.IDS_FeatureNotNullGenericTypeConstraint, diagnostics); 344var diagnosticInfo = diagnostics.Add(ErrorCode.ERR_BadSKknown, syntax.Location, syntax, symbol.Symbol.GetKindText(), MessageID.IDS_SK_TYPE.Localize()); 461MessageID.IDS_FeatureFunctionPointers.CheckFeatureAvailability(diagnostics, functionPointerTypeSyntax.DelegateKeyword); 552MessageID.IDS_FeatureNullable.CheckFeatureAvailability(diagnostics, nullableSyntax.QuestionToken); 589MessageID.IDS_FeatureGlobalNamespace.CheckFeatureAvailability(diagnostics, node.Alias); 629var requiredVersion = MessageID.IDS_FeatureDefaultTypeParameterConstraint.RequiredVersion(); 690MessageID.IDS_FeatureTuples.CheckFeatureAvailability(diagnostics, syntax); 745bool includeNullability = Compilation.IsFeatureEnabled(MessageID.IDS_FeatureNullableReferenceTypes); 943if (Compilation.LanguageVersion < MessageID.IDS_FeatureDynamic.RequiredVersion()) 1034CheckFeatureAvailability(node, MessageID.IDS_FeatureNativeInt, diagnostics); 1381var binder = !Compilation.IsFeatureEnabled(MessageID.IDS_FeatureUsingTypeAlias) 1402CheckFeatureAvailability(typeSyntax, MessageID.IDS_FeatureUnboundGenericTypesInNameof, diagnostics); 1422Error(diagnostics, ErrorCode.ERR_BadArity, typeSyntax, type, MessageID.IDS_SK_TYPE.Localize(), typeArgumentsSyntax.Count); 1454Error(diagnostics, ErrorCode.ERR_BadArity, syntax, plainName, MessageID.IDS_MethodGroup.Localize(), typeArgumentsSyntax.Count); 1644bool includeNullability = Compilation.IsFeatureEnabled(MessageID.IDS_FeatureNullableReferenceTypes); 2822internal static bool CheckFeatureAvailability(SyntaxNodeOrToken syntax, MessageID feature, BindingDiagnosticBag diagnostics, Location? location = null) 2825internal static bool CheckFeatureAvailability(SyntaxNode syntax, MessageID feature, BindingDiagnosticBag diagnostics, Location? location = null) 2828internal static bool CheckFeatureAvailability(SyntaxToken syntax, MessageID feature, BindingDiagnosticBag diagnostics, bool forceWarning = false) 2831internal static bool CheckFeatureAvailability(SyntaxTree tree, MessageID feature, BindingDiagnosticBag diagnostics, Location location) 2834private static bool CheckFeatureAvailability(SyntaxNode syntax, MessageID feature, DiagnosticBag? diagnostics, Location? location = null) 2837private static bool CheckFeatureAvailability(SyntaxToken syntax, MessageID feature, DiagnosticBag? diagnostics, bool forceWarning = false) 2840private static bool CheckFeatureAvailability(SyntaxTree tree, MessageID feature, DiagnosticBag? diagnostics, Location location) 2846private static bool CheckFeatureAvailability<TData>(SyntaxTree tree, MessageID feature, DiagnosticBag? diagnostics, TData data, Func<TData, Location> getLocation, bool forceWarning = false)

275var featureDiag = MessageID.IDS_FeatureUnsafeEvolution.GetFeatureAvailabilityDiagnosticInfo(this.Compilation); 318else if (this.IsIndirectlyInIterator && MessageID.IDS_FeatureRefUnsafeInIteratorAsync.GetFeatureAvailabilityDiagnosticInfo(Compilation) is { } unsafeInIteratorDiagnosticInfo)

17MessageID.IDS_FeatureRecords.CheckFeatureAvailability(diagnostics, syntax.WithKeyword); 32CheckFeatureAvailability(syntax, MessageID.IDS_FeatureWithOnStructs, diagnostics); 36CheckFeatureAvailability(syntax, MessageID.IDS_FeatureWithOnAnonymousTypes, diagnostics);

800MessageID.IDS_FeatureExtensions.CheckFeatureAvailability(diagnostics, syntax); 808MessageID.IDS_FeatureExtensionIndexers.CheckFeatureAvailability(diagnostics, syntax);

52public override MessageID MessageID { get { return MessageID.IDS_FeatureQueryExpression; } } // TODO: what is the correct ID here?

975Error(diagnostics, ErrorCode.ERR_BadSKknown, node, ns.NamespaceSymbol, MessageID.IDS_SK_NAMESPACE.Localize(), MessageID.IDS_SK_VARIABLE.Localize()); 980Error(diagnostics, ErrorCode.ERR_BadSKknown, node, type.Type, MessageID.IDS_SK_TYPE.Localize(), MessageID.IDS_SK_VARIABLE.Localize()); 991Error(diagnostics, GetMethodGroupOrFunctionPointerLvalueError(valueKind), node, unconvertedAddressOf.Operand.Name, MessageID.IDS_AddressOfMethodGroup.Localize()); 1002Error(diagnostics, GetMethodGroupOrFunctionPointerLvalueError(valueKind), node, methodGroup.Name, MessageID.IDS_MethodGroup.Localize()); 1260Error(diagnostics, ErrorCode.ERR_BadSKknown, expr.Syntax, ((BoundNamespaceExpression)expr).NamespaceSymbol, MessageID.IDS_SK_NAMESPACE.Localize(), MessageID.IDS_SK_VARIABLE.Localize()); 1268Error(diagnostics, ErrorCode.ERR_BadSKunknown, expr.Syntax, expr.Type, MessageID.IDS_SK_TYPE.Localize()); 1305else if (this.IsDirectlyInIterator && Compilation.IsFeatureEnabled(MessageID.IDS_FeatureRefUnsafeInIteratorAsync)) 2059CheckFeatureAvailability(node, MessageID.IDS_FeatureInitOnlySetters, diagnostics); 3439MessageID cause; 3442cause = MessageID.IDS_FOREACHLOCAL; 3446cause = MessageID.IDS_USINGLOCAL; 3450cause = MessageID.IDS_FIXEDLOCAL;

137MessageID.IDS_FeatureRefUnsafeInIteratorAsync.CheckFeatureAvailability(diagnostics, compilation, errorLocation);

220CheckFeatureAvailability(_syntax.AwaitKeyword, MessageID.IDS_FeatureAsyncStreams, diagnostics); 243var messageId = IsAsync ? MessageID.IDS_FeatureExtensionGetAsyncEnumerator : MessageID.IDS_FeatureExtensionGetEnumerator; 301MessageID.IDS_FeatureRefForEach.CheckFeatureAvailability(diagnostics, typeSyntax); 545CheckFeatureAvailability(foreachKeyword, MessageID.IDS_FeatureRefUnsafeInIteratorAsync, diagnostics); 903CheckFeatureAvailability(collectionExpr.Syntax, MessageID.IDS_FeatureInlineArrays, diagnostics); 1248CheckFeatureAvailability(expr.Syntax, MessageID.IDS_FeatureDisposalPattern, diagnostics); 1296CheckFeatureAvailability(syntax, MessageID.IDS_FeatureRefStructInterfaces, diagnostics); 1475MessageID patternName = isAsync ? MessageID.IDS_FeatureAsyncStreams : MessageID.IDS_Collection; 1512diagnostics.Add(ErrorCode.WRN_PatternIsAmbiguous, collectionSyntax.Location, patternType, MessageID.IDS_Collection.Localize(), 1610diagnostics.Add(ErrorCode.WRN_PatternIsAmbiguous, collectionSyntax.Location, collectionExpr.Type, MessageID.IDS_Collection.Localize(), 1769diagnostics.Add(ErrorCode.WRN_PatternBadSignature, collectionSyntax.Location, enumeratorType, MessageID.IDS_Collection.Localize(), patternMemberCandidate); 1833CheckFeatureAvailability(collectionSyntax, MessageID.IDS_FeatureRefStructInterfaces, diagnostics);

81MessageID.IDS_FeatureRefFor.CheckFeatureAvailability(diagnostics, type);

61CheckFeatureAvailability(exprSyntax, MessageID.IDS_FeatureLockObject, diagnostics);

204var diagInfo = diagnose ? new CSDiagnosticInfo(ErrorCode.ERR_BadSKknown, unwrappedSymbol.Name, unwrappedSymbol.GetKindText(), MessageID.IDS_SK_TYPE.Localize()) : null;

3969return Compilation?.IsFeatureEnabled(MessageID.IDS_FeatureFirstClassSpan) != false;

1735return _compilation?.IsFeatureEnabled(MessageID.IDS_FeatureFirstClassSpan) != false;

1862if (!Compilation.IsFeatureEnabled(MessageID.IDS_FeatureOverloadResolutionPriority)) 2976if (_binder.Compilation.IsFeatureEnabled(MessageID.IDS_FeatureImprovedInterpolatedStrings) && 3499if (Compilation.IsFeatureEnabled(MessageID.IDS_FeatureFirstClassSpan)) 3985if (argRefKind == RefKind.Ref && binder.Compilation.IsFeatureEnabled(MessageID.IDS_FeatureRefReadonlyParameters)) 4032if (compilation.IsFeatureEnabled(MessageID.IDS_FeatureRefReadonlyParameters) &&

1295!(refArg == RefKind.Ref && refParameter == RefKind.In && binder.Compilation.IsFeatureEnabled(MessageID.IDS_FeatureRefReadonlyParameters)) && 1306else if (refArg == RefKind.Ref && refParameter == RefKind.In && !binder.Compilation.IsFeatureEnabled(MessageID.IDS_FeatureRefReadonlyParameters)) 1315new CSharpRequiredLanguageVersion(MessageID.IDS_FeatureRefReadonlyParameters.RequiredVersion()));

281MessageID.IDS_FeaturePatternMatching.CheckFeatureAvailability(diagnostics, node.Keyword);

39((CSharpParseOptions)SwitchSyntax.SyntaxTree.Options)?.IsFeatureEnabled(MessageID.IDS_FeaturePatternMatching) != false; 425CheckFeatureAvailability(node, MessageID.IDS_FeatureSwitchOnBool, diagnostics);

98CheckFeatureAvailability(usingKeyword, MessageID.IDS_FeatureUsingDeclarations, diagnostics); 102CheckFeatureAvailability(awaitKeyword, MessageID.IDS_FeatureAsyncUsing, diagnostics); 207MessageID.IDS_FeatureDisposalPattern.CheckFeatureAvailability(diagnostics, originalBinder.Compilation, syntax.Location); 304CheckFeatureAvailability(syntax, MessageID.IDS_FeatureRefStructInterfaces, diagnostics);

39get { return ConstantValueOpt?.IsNull == true ? MessageID.IDS_NULL.Localize() : base.Display; } 63get { return MessageID.IDS_MethodGroup.Localize(); } 71get { return MessageID.IDS_ThrowExpression.Localize(); } 161=> (Type is null) ? MessageID.IDS_FeatureSwitchExpression.Localize() : base.Display; 167=> (Type is null) ? MessageID.IDS_FeatureTargetTypedConditional.Localize() : base.Display; 173=> (Type is null) ? MessageID.IDS_CollectionExpression.Localize() : base.Display;

75public MessageID MessageID { get { return Syntax.Kind() == SyntaxKind.AnonymousMethodExpression ? MessageID.IDS_AnonMethod : MessageID.IDS_Lambda; } } 465public MessageID MessageID { get { return Data.MessageID; } } 590public abstract MessageID MessageID { get; } 1561public override MessageID MessageID { get { return this.UnboundLambda.Syntax.Kind() == SyntaxKind.AnonymousMethodExpression ? MessageID.IDS_AnonMethod : MessageID.IDS_Lambda; } }

211AddDiagnostic(diagnostics, ErrorCode.ERR_SwitchNeedsString, MessageID.IDS_Text.Localize(), "/langversion:"); 283ParseAndResolveReferencePaths(name, valueMemory, baseDirectory, libPaths, MessageID.IDS_LIB_OPTION, diagnostics); 346ParseAndResolveReferencePaths(name, valueMemory, baseDirectory, sourcePaths, MessageID.IDS_REFERENCEPATH_OPTION, diagnostics); 434AddDiagnostic(diagnostics, ErrorCode.ERR_SwitchNeedsString, MessageID.IDS_Text.Localize(), name); 648AddDiagnostic(diagnostics, ErrorCode.ERR_SwitchNeedsString, MessageID.IDS_Text.Localize(), "modulename"); 696AddDiagnostic(diagnostics, ErrorCode.ERR_SwitchNeedsString, MessageID.IDS_Text.Localize(), arg); 709AddDiagnostic(diagnostics, ErrorCode.ERR_SwitchNeedsString, MessageID.IDS_Text.Localize(), arg); 717AddDiagnostic(diagnostics, ErrorCode.ERR_SwitchNeedsString, MessageID.IDS_Text.Localize(), "/doc:"); // Different argument. 729AddDiagnostic(diagnostics, ErrorCode.ERR_SwitchNeedsString, MessageID.IDS_Text.Localize(), "/addmodule:"); 819AddDiagnostic(diagnostics, ErrorCode.ERR_SwitchNeedsString, MessageID.IDS_Text.Localize(), name); 1076AddDiagnostic(diagnostics, ErrorCode.ERR_SwitchNeedsString, MessageID.IDS_Text.Localize(), "keycontainer"); 1138AddDiagnostic(diagnostics, ErrorCode.ERR_SwitchNeedsString, MessageID.IDS_Text.Localize(), "subsystemversion"); 1159AddDiagnostic(diagnostics, ErrorCode.ERR_SwitchNeedsString, MessageID.IDS_Text.Localize(), "touchedfiles"); 1454ParseAndResolveReferencePaths(null, additionalReferenceDirectories.AsMemory(), baseDirectory, libPaths, MessageID.IDS_LIB_ENV, diagnostics); 1569if (nullableContextOptions != NullableContextOptions.Disable && parseOptions.LanguageVersion < MessageID.IDS_FeatureNullableReferenceTypes.RequiredVersion()) 1573new CSharpRequiredLanguageVersion(MessageID.IDS_FeatureNullableReferenceTypes.RequiredVersion())), Location.None)); 1632private static void ParseAndResolveReferencePaths(string? switchName, ReadOnlyMemory<char>? switchValue, string? baseDirectory, List<string> builder, MessageID origin, List<Diagnostic> diagnostics) 1637AddDiagnostic(diagnostics, ErrorCode.ERR_SwitchNeedsString, MessageID.IDS_PathList.Localize(), switchName); 1646AddDiagnostic(diagnostics, ErrorCode.WRN_InvalidSearchPathDir, path, origin.Localize(), MessageID.IDS_DirectoryHasInvalidPath.Localize()); 1650AddDiagnostic(diagnostics, ErrorCode.WRN_InvalidSearchPathDir, path, origin.Localize(), MessageID.IDS_DirectoryDoesNotExist.Localize()); 1891AddDiagnostic(diagnostics, ErrorCode.ERR_SwitchNeedsString, MessageID.IDS_Namespace1.Localize(), arg); 1905AddDiagnostic(diagnostics, ErrorCode.ERR_SwitchNeedsString, MessageID.IDS_Text.Localize(), arg); 1932AddDiagnostic(diagnostics, ErrorCode.ERR_SwitchNeedsString, MessageID.IDS_Text.Localize(), arg);

277consoleOutput.WriteLine(ErrorFacts.GetMessage(MessageID.IDS_LogoLine1, Culture), GetToolName(), GetCompilerVersion()); 278consoleOutput.WriteLine(ErrorFacts.GetMessage(MessageID.IDS_LogoLine2, Culture)); 284consoleOutput.WriteLine(ErrorFacts.GetMessage(MessageID.IDS_LangVersions, Culture)); 316return ErrorFacts.GetMessage(MessageID.IDS_ToolName, Culture); 325consoleOutput.WriteLine(ErrorFacts.GetMessage(MessageID.IDS_CSCHelp, Culture));

2131CheckFeatureAvailability(Candidate.ExtractReturnTypeSyntax(), MessageID.IDS_FeatureAsyncMain, diagnostics)) 2138else if (LanguageVersion >= MessageID.IDS_FeatureAsyncMain.RequiredVersion() && taskEntryPoints.Count > 0) 3094if (Options.NullableContextOptions != NullableContextOptions.Disable && LanguageVersion < MessageID.IDS_FeatureNullableReferenceTypes.RequiredVersion() && 3099new CSharpRequiredLanguageVersion(MessageID.IDS_FeatureNullableReferenceTypes.RequiredVersion())), Location.None)); 3102if (Options.UseUpdatedMemorySafetyRules && !this.IsFeatureEnabled(MessageID.IDS_FeatureUnsafeEvolution)) 3106new CSharpRequiredLanguageVersion(MessageID.IDS_FeatureUnsafeEvolution.RequiredVersion())), Location.None));

12internal static bool IsFeatureEnabled(this CSharpCompilation compilation, MessageID feature) 17internal static bool IsFeatureEnabled(this SyntaxNode? syntax, MessageID feature)

322string message = ErrorFacts.GetMessage(MessageID.IDS_XMLIGNORED, CultureInfo.CurrentUICulture); 431string message = ErrorFacts.GetMessage(MessageID.IDS_XMLIGNORED, CultureInfo.CurrentUICulture); 550string message = ErrorFacts.GetMessage(MessageID.IDS_XMLIGNORED, CultureInfo.CurrentUICulture);

283_diagnostics.Add(ErrorCode.WRN_FailedInclude, location, filePathValue, xpathValue, new LocalizableErrorArgument(MessageID.IDS_OperationCausedStackOverflow)); 286commentMessage = ErrorFacts.GetMessage(MessageID.IDS_XMLNOINCLUDE, CultureInfo.CurrentUICulture); 303var subMessage = hasFileAttribute ? MessageID.IDS_XMLMISSINGINCLUDEPATH.Localize() : MessageID.IDS_XMLMISSINGINCLUDEFILE.Localize(); 305commentMessage = MakeCommentMessage(location, MessageID.IDS_XMLBADINCLUDE); 316commentMessage = MakeCommentMessage(location, MessageID.IDS_XMLFAILEDINCLUDE); 326commentMessage = MakeCommentMessage(location, MessageID.IDS_XMLFAILEDINCLUDE); 347commentMessage = MakeCommentMessage(location, MessageID.IDS_XMLFAILEDINCLUDE); 360commentMessage = MakeCommentMessage(location, MessageID.IDS_XMLFAILEDINCLUDE); 396commentMessage = MakeCommentMessage(location, MessageID.IDS_XMLNOINCLUDE); 409commentMessage = string.Format(ErrorFacts.GetMessage(MessageID.IDS_XMLIGNORED2, CultureInfo.CurrentUICulture), resolvedFilePath); 434private static string MakeCommentMessage(Location location, MessageID messageId)

642_compilation.LanguageVersion >= MessageID.IDS_FeatureNullableReferenceTypes.RequiredVersion() && 1964var isSufficientLangVersion = compilation.LanguageVersion >= MessageID.IDS_FeatureNullableReferenceTypes.RequiredVersion();

273internal bool IsFeatureEnabled(MessageID feature)

482MessageID.IDS_FeatureUsingStatic.CheckFeatureAvailability(diagnostics, usingDirective, usingDirective.StaticKeyword.GetLocation()); 485MessageID.IDS_FeatureGlobalUsing.CheckFeatureAvailability(diagnostics, usingDirective, usingDirective.GlobalKeyword.GetLocation()); 492MessageID.IDS_FeatureExternAlias.CheckFeatureAvailability(diagnostics, externAlias, externAlias.ExternKeyword.GetLocation()); 530MessageID.IDS_FeatureFileScopedNamespace.CheckFeatureAvailability(diagnostics, node, node.NamespaceKeyword.GetLocation()); 761MessageID.IDS_FeatureRecordStructs.CheckFeatureAvailability(diagnostics, record, record.ClassOrStructKeyword.GetLocation()); 774MessageID.IDS_FeaturePrimaryConstructors.CheckFeatureAvailability(diagnostics, node.ParameterList); 779MessageID.IDS_FeaturePrimaryConstructors.CheckFeatureAvailability(diagnostics, node, node.SemicolonToken.GetLocation()); 784MessageID.IDS_FeatureUnions.CheckFeatureAvailability(diagnostics, node, node.Keyword.GetLocation()); 796MessageID.IDS_FeatureStaticClasses.CheckFeatureAvailability(diagnostics, node, modifier.GetLocation()); 800MessageID.IDS_FeatureReadOnlyStructs.CheckFeatureAvailability(diagnostics, node, modifier.GetLocation()); 804MessageID.IDS_FeatureRefStructs.CheckFeatureAvailability(diagnostics, node, modifier.GetLocation()); 894MessageID.IDS_FeaturePrimaryConstructors.CheckFeatureAvailability(diagnostics, node, node.SemicolonToken.GetLocation());

135public static string GetMessage(MessageID code, CultureInfo culture)

66const MessageID featureId = MessageID.IDS_FeatureNullableReferenceTypes;

323private readonly MessageID _id; 325internal LocalizableErrorArgument(MessageID id) 345public static LocalizableErrorArgument Localize(this MessageID id) 356internal static string? RequiredFeature(this MessageID feature) 367this MessageID feature, 381this MessageID feature, 395this MessageID feature, 409this MessageID feature, 423this MessageID feature, 438this MessageID feature, 453this MessageID feature, 466internal static CSDiagnosticInfo? GetFeatureAvailabilityDiagnosticInfo(this MessageID feature, CSharpParseOptions options) 469internal static CSDiagnosticInfo? GetFeatureAvailabilityDiagnosticInfo(this MessageID feature, CSharpCompilation compilation) 472private static CSDiagnosticInfo GetDisabledFeatureDiagnosticInfo(MessageID feature, LanguageVersion availableVersion) 486internal static LanguageVersion RequiredVersion(this MessageID feature) 497case MessageID.IDS_FeatureUnsafeEvolution: // https://github.com/dotnet/roslyn/issues/82546: keep this in preview until C# 16 501case MessageID.IDS_FeatureCollectionExpressionArguments: 502case MessageID.IDS_FeatureUnions: 503case MessageID.IDS_FeatureStaticMembersInInterfaces: 504case MessageID.IDS_FeatureClosedClasses: // semantic check 505case MessageID.IDS_FeatureLabeledBreakContinue: 506case MessageID.IDS_FeatureExtensionIndexers: 510case MessageID.IDS_FeatureFieldKeyword: 511case MessageID.IDS_FeatureFirstClassSpan: 512case MessageID.IDS_FeatureUnboundGenericTypesInNameof: 513case MessageID.IDS_FeatureSimpleLambdaParameterModifiers: 514case MessageID.IDS_FeaturePartialEventsAndConstructors: 515case MessageID.IDS_FeatureExtensions: 516case MessageID.IDS_FeatureNullConditionalAssignment: 517case MessageID.IDS_FeatureExpressionOptionalAndNamedArguments: 518case MessageID.IDS_FeatureUserDefinedCompoundAssignmentOperators: 522case MessageID.IDS_FeatureStringEscapeCharacter: // lexer check 523case MessageID.IDS_FeatureImplicitIndexerInitializer: 524case MessageID.IDS_FeatureLockObject: 525case MessageID.IDS_FeatureParamsCollections: 526case MessageID.IDS_FeatureRefUnsafeInIteratorAsync: 527case MessageID.IDS_FeatureRefStructInterfaces: 528case MessageID.IDS_FeatureAllowsRefStructConstraint: 529case MessageID.IDS_FeaturePartialProperties: 530case MessageID.IDS_FeatureOverloadResolutionPriority: 534case MessageID.IDS_FeatureLambdaOptionalParameters: // semantic check 535case MessageID.IDS_FeatureLambdaParamsArray: // semantic check 536case MessageID.IDS_FeaturePrimaryConstructors: // declaration table check 537case MessageID.IDS_FeatureUsingTypeAlias: // semantic check 538case MessageID.IDS_FeatureInstanceMemberInNameof: // semantic check 539case MessageID.IDS_FeatureInlineArrays: // semantic check 540case MessageID.IDS_FeatureCollectionExpressions: // semantic check 541case MessageID.IDS_FeatureRefReadonlyParameters: // semantic check 545case MessageID.IDS_FeatureRawStringLiterals: 546case MessageID.IDS_FeatureStaticAbstractMembersInInterfaces: // semantic check 547case MessageID.IDS_FeatureNewLinesInInterpolations: // semantic check 548case MessageID.IDS_FeatureListPattern: // semantic check 549case MessageID.IDS_FeatureRequiredMembers: // semantic check 550case MessageID.IDS_FeatureCacheStaticMethodGroupConversion: // lowering check 551case MessageID.IDS_FeatureSpanCharConstantPattern: 552case MessageID.IDS_FeatureAutoDefaultStructs: // semantic check 553case MessageID.IDS_FeatureCheckedUserDefinedOperators: // semantic check for declarations, parsing check for doc comments 554case MessageID.IDS_FeatureUtf8StringLiterals: // semantic check 555case MessageID.IDS_FeatureUnsignedRightShift: // semantic check for declarations and consumption, parsing check for doc comments 556case MessageID.IDS_FeatureRelaxedShiftOperator: // semantic check 557case MessageID.IDS_FeatureRefFields: // semantic check 558case MessageID.IDS_FeatureFileTypes: // semantic check 559case MessageID.IDS_FeatureGenericAttributes: // semantic check 563case MessageID.IDS_FeatureMixedDeclarationsAndExpressionsInDeconstruction: // semantic check 564case MessageID.IDS_FeatureSealedToStringInRecord: // semantic check 565case MessageID.IDS_FeatureImprovedInterpolatedStrings: // semantic check 566case MessageID.IDS_FeatureRecordStructs: 567case MessageID.IDS_FeatureWithOnStructs: // semantic check 568case MessageID.IDS_FeatureWithOnAnonymousTypes: // semantic check 569case MessageID.IDS_FeaturePositionalFieldsInRecords: // semantic check 570case MessageID.IDS_FeatureGlobalUsing: 571case MessageID.IDS_FeatureInferredDelegateType: // semantic check 572case MessageID.IDS_FeatureLambdaAttributes: // semantic check 573case MessageID.IDS_FeatureExtendedPropertyPatterns: // semantic check 574case MessageID.IDS_FeatureLambdaReturnType: // semantic check 575case MessageID.IDS_AsyncMethodBuilderOverride: // semantic check 576case MessageID.IDS_FeatureConstantInterpolatedStrings: // semantic check 577case MessageID.IDS_FeatureImplicitImplementationOfNonPublicMembers: // semantic check 578case MessageID.IDS_FeatureFileScopedNamespace: // semantic check 579case MessageID.IDS_FeatureParameterlessStructConstructors: // semantic check 580case MessageID.IDS_FeatureStructFieldInitializers: // semantic check 584case MessageID.IDS_FeatureLambdaDiscardParameters: // semantic check 585case MessageID.IDS_FeatureFunctionPointers: // semantic check 586case MessageID.IDS_FeatureLocalFunctionAttributes: // syntax check 587case MessageID.IDS_FeatureExternLocalFunctions: // semantic check 588case MessageID.IDS_FeatureImplicitObjectCreation: // semantic check 589case MessageID.IDS_FeatureMemberNotNull: 590case MessageID.IDS_FeatureAndPattern: // semantic check 591case MessageID.IDS_FeatureNotPattern: // semantic check 592case MessageID.IDS_FeatureOrPattern: // semantic check 593case MessageID.IDS_FeatureParenthesizedPattern: // semantic check 594case MessageID.IDS_FeatureTypePattern: // semantic check 595case MessageID.IDS_FeatureRelationalPattern: // semantic check 596case MessageID.IDS_FeatureExtensionGetEnumerator: // semantic check 597case MessageID.IDS_FeatureExtensionGetAsyncEnumerator: // semantic check 598case MessageID.IDS_FeatureNativeInt: 599case MessageID.IDS_FeatureExtendedPartialMethods: // semantic check 600case MessageID.IDS_TopLevelStatements: 601case MessageID.IDS_FeatureInitOnlySetters: // semantic check 602case MessageID.IDS_FeatureRecords: // semantic check 603case MessageID.IDS_FeatureTargetTypedConditional: // semantic check 604case MessageID.IDS_FeatureCovariantReturnsForOverrides: // semantic check 605case MessageID.IDS_FeatureStaticAnonymousFunction: // semantic check 606case MessageID.IDS_FeatureModuleInitializers: // semantic check on method attribute 607case MessageID.IDS_FeatureDefaultTypeParameterConstraint: // semantic check 608case MessageID.IDS_FeatureVarianceSafetyForStaticInterfaceMembers: // semantic check 612case MessageID.IDS_FeatureAltInterpolatedVerbatimStrings: // semantic check 613case MessageID.IDS_FeatureCoalesceAssignmentExpression: // semantic check 614case MessageID.IDS_FeatureUnconstrainedTypeParameterInNullCoalescingOperator: 615case MessageID.IDS_FeatureNullableReferenceTypes: // syntax and semantic check 616case MessageID.IDS_FeatureIndexOperator: // semantic check 617case MessageID.IDS_FeatureRangeOperator: // semantic check 618case MessageID.IDS_FeatureAsyncStreams: // semantic check 619case MessageID.IDS_FeatureRecursivePatterns: // semantic check 620case MessageID.IDS_FeatureUsingDeclarations: // semantic check 621case MessageID.IDS_FeatureDisposalPattern: //semantic check 622case MessageID.IDS_FeatureStaticLocalFunctions: // semantic check 623case MessageID.IDS_FeatureNameShadowingInNestedFunctions: 624case MessageID.IDS_FeatureUnmanagedConstructedTypes: // semantic check 625case MessageID.IDS_FeatureObsoleteOnPropertyAccessor: 626case MessageID.IDS_FeatureReadOnlyMembers: 627case MessageID.IDS_DefaultInterfaceImplementation: // semantic check 628case MessageID.IDS_OverrideWithConstraints: // semantic check 629case MessageID.IDS_FeatureNestedStackalloc: // semantic check 630case MessageID.IDS_FeatureNotNullGenericTypeConstraint:// semantic check 631case MessageID.IDS_FeatureSwitchExpression: 632case MessageID.IDS_FeatureAsyncUsing: 633case MessageID.IDS_FeatureNullPointerConstantPattern: //semantic check 637case MessageID.IDS_FeatureAttributesOnBackingFields: // semantic check 638case MessageID.IDS_FeatureImprovedOverloadCandidates: // semantic check 639case MessageID.IDS_FeatureTupleEquality: // semantic check 640case MessageID.IDS_FeatureRefReassignment: // semantic check 641case MessageID.IDS_FeatureRefFor: 642case MessageID.IDS_FeatureRefForEach: // semantic check 643case MessageID.IDS_FeatureEnumGenericTypeConstraint: // semantic check 644case MessageID.IDS_FeatureDelegateGenericTypeConstraint: // semantic check 645case MessageID.IDS_FeatureUnmanagedGenericTypeConstraint: // semantic check 646case MessageID.IDS_FeatureStackAllocInitializer: // semantic check 647case MessageID.IDS_FeatureExpressionVariablesInQueriesAndInitializers: // semantic check 648case MessageID.IDS_FeatureExtensibleFixedStatement: // semantic check 649case MessageID.IDS_FeatureIndexingMovableFixedBuffers: //semantic check 653case MessageID.IDS_FeatureNonTrailingNamedArguments: // semantic check 654case MessageID.IDS_FeatureLeadingDigitSeparator: 655case MessageID.IDS_FeaturePrivateProtected: 656case MessageID.IDS_FeatureReadOnlyReferences: // semantic check 657case MessageID.IDS_FeatureRefStructs: // semantic check 658case MessageID.IDS_FeatureReadOnlyStructs: // semantic check 659case MessageID.IDS_FeatureRefExtensionMethods: 660case MessageID.IDS_FeatureRefConditional: 664case MessageID.IDS_FeatureAsyncMain: 665case MessageID.IDS_FeatureDefaultLiteral: // semantic check 666case MessageID.IDS_FeatureInferredTupleNames: 667case MessageID.IDS_FeatureGenericPatternMatching: 671case MessageID.IDS_FeatureBinaryLiteral: 672case MessageID.IDS_FeatureDigitSeparator: 673case MessageID.IDS_FeatureLocalFunctions: // semantic check 674case MessageID.IDS_FeatureRefLocalsReturns: 675case MessageID.IDS_FeaturePatternMatching: // semantic check 676case MessageID.IDS_FeatureThrowExpression: // semantic check 677case MessageID.IDS_FeatureTuples: 678case MessageID.IDS_FeatureOutVar: // semantic check 679case MessageID.IDS_FeatureExpressionBodiedAccessor: 680case MessageID.IDS_FeatureExpressionBodiedDeOrConstructor: 681case MessageID.IDS_FeatureDiscards: 685case MessageID.IDS_FeatureExceptionFilter: // semantic check 686case MessageID.IDS_FeatureAutoPropertyInitializer: // semantic check 687case MessageID.IDS_FeatureNullPropagatingOperator: // semantic check 688case MessageID.IDS_FeatureExpressionBodiedMethod: 689case MessageID.IDS_FeatureExpressionBodiedProperty: // semantic check 690case MessageID.IDS_FeatureExpressionBodiedIndexer: // semantic check 691case MessageID.IDS_FeatureNameof: 692case MessageID.IDS_FeatureDictionaryInitializer: // semantic check 693case MessageID.IDS_FeatureUsingStatic: // semantic check 694case MessageID.IDS_FeatureInterpolatedStrings: // semantic check 695case MessageID.IDS_AwaitInCatchAndFinally: 696case MessageID.IDS_FeatureReadonlyAutoImplementedProperties: 700case MessageID.IDS_FeatureAsync: // semantic check 704case MessageID.IDS_FeatureDynamic: // Checked in the binder. 705case MessageID.IDS_FeatureTypeVariance: // semantic check 706case MessageID.IDS_FeatureNamedArgument: // semantic check 707case MessageID.IDS_FeatureOptionalParameter: // semantic check 711case MessageID.IDS_FeatureImplicitArray: // semantic check 712case MessageID.IDS_FeatureAnonymousTypes: // semantic check 713case MessageID.IDS_FeatureObjectInitializer: 714case MessageID.IDS_FeatureCollectionInitializer: 715case MessageID.IDS_FeatureLambda: // semantic check 716case MessageID.IDS_FeatureQueryExpression: // semantic check 717case MessageID.IDS_FeatureExtensionMethod: 718case MessageID.IDS_FeaturePartialMethod: // semantic check 719case MessageID.IDS_FeatureImplicitLocal: // Checked in the binder. 720case MessageID.IDS_FeatureAutoImplementedProperties: 724case MessageID.IDS_FeatureGenerics: // Also affects crefs. 725case MessageID.IDS_FeatureAnonDelegates: // semantic check 726case MessageID.IDS_FeatureGlobalNamespace: // Also affects crefs. 727case MessageID.IDS_FeatureFixedBuffer: // semantic check 728case MessageID.IDS_FeatureStaticClasses: // semantic check 729case MessageID.IDS_FeaturePartialTypes: // semantic check 730case MessageID.IDS_FeaturePropertyAccessorMods: 731case MessageID.IDS_FeatureExternAlias: // semantic check 732case MessageID.IDS_FeatureIterators: // semantic check 733case MessageID.IDS_FeatureDefault: // semantic check 734case MessageID.IDS_FeatureNullable: 735case MessageID.IDS_FeaturePragma: // Checked in the directive parser. 736case MessageID.IDS_FeatureSwitchOnBool: // Checked in the binder. 740case MessageID.IDS_FeatureModuleAttrLoc:

96if (compilation.LanguageVersion >= MessageID.IDS_FeatureRecursivePatterns.RequiredVersion())

447if (compilation.IsFeatureEnabled(MessageID.IDS_FeatureAutoDefaultStructs)) 460new CSharpRequiredLanguageVersion(MessageID.IDS_FeatureAutoDefaultStructs.RequiredVersion())); 472if (!compilation.IsFeatureEnabled(MessageID.IDS_FeatureAutoDefaultStructs)) 1246if (compilation.IsFeatureEnabled(MessageID.IDS_FeatureAutoDefaultStructs)) 1255new CSharpRequiredLanguageVersion(MessageID.IDS_FeatureAutoDefaultStructs.RequiredVersion())); 1298else if (compilation.IsFeatureEnabled(MessageID.IDS_FeatureAutoDefaultStructs)) 1311new CSharpRequiredLanguageVersion(MessageID.IDS_FeatureAutoDefaultStructs.RequiredVersion()));

952|| compilation.IsFeatureEnabled(MessageID.IDS_FeatureAutoDefaultStructs))) 1757return compilation.LanguageVersion >= MessageID.IDS_FeatureNullableReferenceTypes.RequiredVersion(); 2511var requiredVersion = MessageID.IDS_FeatureDefaultTypeParameterConstraint.RequiredVersion();

612return self < MessageID.IDS_FeatureInferredTupleNames.RequiredVersion(); 617return self >= MessageID.IDS_FeatureNonTrailingNamedArguments.RequiredVersion(); 622return self >= MessageID.IDS_FeatureAttributesOnBackingFields.RequiredVersion(); 627return self >= MessageID.IDS_FeatureImprovedOverloadCandidates.RequiredVersion();

335!_compilation.IsFeatureEnabled(MessageID.IDS_FeatureExpressionOptionalAndNamedArguments)) 340!_compilation.IsFeatureEnabled(MessageID.IDS_FeatureExpressionOptionalAndNamedArguments)) 347Debug.Assert(_compilation.IsFeatureEnabled(MessageID.IDS_FeatureExpressionOptionalAndNamedArguments));

586if (_factory.Compilation.LanguageVersion >= MessageID.IDS_FeatureCacheStaticMethodGroupConversion.RequiredVersion()

543token = CheckFeatureAvailability(token, MessageID.IDS_FeatureNullableReferenceTypes); 571pragma = CheckFeatureAvailability(pragma, MessageID.IDS_FeaturePragma);

1068operatorToken = CheckFeatureAvailability(operatorToken, MessageID.IDS_FeatureUnsignedRightShift, forceWarning: true); 1078operatorToken = CheckFeatureAvailability(operatorToken, MessageID.IDS_FeatureUserDefinedCompoundAssignmentOperators, forceWarning: true); 1110operatorToken = CheckFeatureAvailability(operatorToken, MessageID.IDS_FeatureUserDefinedCompoundAssignmentOperators, forceWarning: true); 1169operatorToken = CheckFeatureAvailability(operatorToken, MessageID.IDS_FeatureUserDefinedCompoundAssignmentOperators, forceWarning: true); 1183checkedKeyword = CheckFeatureAvailability(checkedKeyword, MessageID.IDS_FeatureCheckedUserDefinedOperators, forceWarning: true); 1398open = CheckFeatureAvailability(open, MessageID.IDS_FeatureGenerics, forceWarning: true); 1462alias = CheckFeatureAvailability(alias, MessageID.IDS_FeatureGlobalNamespace, forceWarning: true);

1442if (!parseAsModifier(MessageID.IDS_FeatureFileTypes, out modTok)) 1448if (!parseAsModifier(MessageID.IDS_FeatureClosedClasses, out modTok)) 1463if (!parseAsModifier(MessageID.IDS_FeatureRequiredMembers, out modTok)) 1469if (!parseAsModifier(MessageID.IDS_FeatureUnsafeEvolution, out modTok)) 1527bool parseAsModifier(MessageID requiredFeature, [NotNullWhen(true)] out SyntaxToken? modTok) 1686SyntaxKind.RecordKeyword => IsFeatureEnabled(MessageID.IDS_FeatureRecords), 1687SyntaxKind.UnionKeyword => IsFeatureEnabled(MessageID.IDS_FeatureUnions), 1732return IsFeatureEnabled(MessageID.IDS_FeaturePartialEventsAndConstructors); 3411(IsFeatureEnabled(MessageID.IDS_FeatureExtensions) || this.PeekToken(1).Kind == SyntaxKind.LessThanToken); 4744IsFeatureEnabled(MessageID.IDS_FeatureExpressionBodiedAccessor) 6125IsFeatureEnabled(MessageID.IDS_FeatureFieldKeyword); 6574open = CheckFeatureAvailability(open, MessageID.IDS_FeatureGenerics); 9097IsFeatureEnabled(MessageID.IDS_FeatureExpressionBodiedAccessor) 10618if (isLambdaParameter && IsFeatureEnabled(MessageID.IDS_FeatureSimpleLambdaParameterModifiers))

155var info = MessageID.IDS_FeatureStringEscapeCharacter.GetFeatureAvailabilityDiagnosticInfo(this.Options);

780private void CheckFeatureAvailability(MessageID feature) 872CheckFeatureAvailability(MessageID.IDS_FeatureBinaryLiteral); 1028CheckFeatureAvailability(MessageID.IDS_FeatureLeadingDigitSeparator); 1032CheckFeatureAvailability(MessageID.IDS_FeatureDigitSeparator);

1147protected TNode CheckFeatureAvailability<TNode>(TNode node, MessageID feature, bool forceWarning = false) 1165protected bool IsFeatureEnabled(MessageID feature)

377MessageID.IDS_FeatureUsingTypeAlias.CheckFeatureAvailability(diagnostics, usingDirective.UnsafeKeyword); 381MessageID.IDS_FeatureUsingTypeAlias.CheckFeatureAvailability(diagnostics, usingDirective.NamespaceOrType); 396if (!DeclaringCompilation.IsFeatureEnabled(MessageID.IDS_FeatureUsingTypeAlias)) 420MessageID.IDS_FeatureUsingTypeAlias.CheckFeatureAvailability(diagnostics, usingDirective.NamespaceOrType);

10/// Member safety as defined by the unsafe evolution feature (<see cref="MessageID.IDS_FeatureUnsafeEvolution"/>).

158Binder.CheckFeatureAvailability(node.Syntax, MessageID.IDS_FeatureConstantInterpolatedStrings, diagnostics);

102Binder.CheckFeatureAvailability(location.SourceTree, MessageID.IDS_FeatureAllowsRefStructConstraint, diagnostics, location); 495bool includeNullability = compilation.IsFeatureEnabled(MessageID.IDS_FeatureNullableReferenceTypes); 536this(currentCompilation, conversions, currentCompilation.IsFeatureEnabled(MessageID.IDS_FeatureNullableReferenceTypes), location, diagnostics) 970if (MessageID.IDS_FeatureAllowsRefStructConstraint.GetFeatureAvailabilityDiagnosticInfo(args.CurrentCompilation) is { } diagnosticInfo) 1029var csDiagnosticInfo = MessageID.IDS_FeatureUnmanagedConstructedTypes.GetFeatureAvailabilityDiagnosticInfo(args.CurrentCompilation);

47return syntax.IsFeatureEnabled(MessageID.IDS_FeatureInferredDelegateType) ?

20private readonly MessageID _messageID; 78public MessageID MessageID { get { return _messageID; } }

64MessageID.IDS_FeatureUnsafeEvolution.CheckFeatureAvailability(diagnostics, safeToken, safeToken == default ? syntax.Identifier.GetLocation() : null); 448var diagnosticInfo = MessageID.IDS_FeatureLocalFunctionAttributes.GetFeatureAvailabilityDiagnosticInfo((CSharpParseOptions)syntaxReferenceOpt.SyntaxTree.Options);

33modifierErrors |= !MessageID.IDS_FeatureReadOnlyMembers.CheckFeatureAvailability(diagnostics, readonlyToken); 112checkFeature(DeclarationModifiers.PrivateProtected, MessageID.IDS_FeaturePrivateProtected) | 113checkFeature(DeclarationModifiers.Required, MessageID.IDS_FeatureRequiredMembers) | 114checkFeature(DeclarationModifiers.File, MessageID.IDS_FeatureFileTypes) | 115checkFeature(DeclarationModifiers.Closed, MessageID.IDS_FeatureClosedClasses) | 116checkFeature(DeclarationModifiers.Async, MessageID.IDS_FeatureAsync); 122? !Binder.CheckFeatureAvailability(errorLocation.SourceTree, MessageID.IDS_FeatureUnsafeEvolution, diagnostics, errorLocation) 123: !MessageID.IDS_FeatureUnsafeEvolution.CheckFeatureAvailability(diagnostics, safeToken); 135bool checkFeature(DeclarationModifiers modifier, MessageID featureID) 143if (MessageID.IDS_FeatureRefFields.GetFeatureAvailabilityDiagnosticInfo((CSharpParseOptions)syntax.SyntaxTree.Options) is { } diagnosticInfo) 172requiredVersion = MessageID.IDS_FeatureStaticAbstractMembersInInterfaces.RequiredVersion(); 185Binder.CheckFeatureAvailability(errorLocation.SourceTree, MessageID.IDS_DefaultInterfaceImplementation, diagnostics, errorLocation); 190requiredVersion = MessageID.IDS_DefaultInterfaceImplementation.RequiredVersion(); 223LanguageVersion requiredVersion = MessageID.IDS_FeatureStaticAbstractMembersInInterfaces.RequiredVersion(); 237LanguageVersion requiredVersion = MessageID.IDS_FeaturePartialEventsAndConstructors.RequiredVersion(); 485var messageId = SyntaxFacts.IsTypeDeclaration(partialToken.Parent.Kind()) ? MessageID.IDS_FeaturePartialTypes : MessageID.IDS_FeaturePartialMethod;

228bool allowShadowingNames = withTypeParametersBinder.Compilation.IsFeatureEnabled(MessageID.IDS_FeatureNameShadowingInNestedFunctions) && 607Binder.CheckFeatureAvailability(modifier, MessageID.IDS_FeatureExtensionMethod, diagnostics); 611Binder.CheckFeatureAvailability(modifier, MessageID.IDS_FeatureRefExtensionMethods, diagnostics); 640Binder.CheckFeatureAvailability(modifier, MessageID.IDS_FeatureRefExtensionMethods, diagnostics); 728MessageID.IDS_FeatureLambdaParamsArray.CheckFeatureAvailability(diagnostics, modifier); 738Binder.CheckFeatureAvailability(modifier, MessageID.IDS_FeatureReadOnlyReferences, diagnostics); 742Binder.CheckFeatureAvailability(modifier, MessageID.IDS_FeatureRefExtensionMethods, diagnostics); 805Binder.CheckFeatureAvailability(modifier, MessageID.IDS_FeatureRefReadonlyParameters, diagnostics);

384MessageID.IDS_FeatureOptionalParameter.CheckFeatureAvailability(diagnostics, defaultSyntax.EqualsToken); 1722MessageID.IDS_FeatureParamsCollections.CheckFeatureAvailability(diagnostics, ParameterSyntax);

52bool reported = !MessageID.IDS_FeatureExtensions.CheckFeatureAvailability(diagnostics, syntax);

151Binder.CheckFeatureAvailability(syntax, MessageID.IDS_DefaultInterfaceImplementation, diagnostics, this.GetFirstLocation());

1032else if (MessageID.IDS_FeatureCovariantReturnsForOverrides.GetFeatureAvailabilityDiagnosticInfo(this.DeclaringCompilation) is { } diagnosticInfo) 1104var diagnosticInfo = MessageID.IDS_FeatureCovariantReturnsForOverrides.GetFeatureAvailabilityDiagnosticInfo(this.DeclaringCompilation); 1237DeclaringCompilation.LanguageVersion >= MessageID.IDS_FeatureCovariantReturnsForOverrides.RequiredVersion()) 1598compilation.IsFeatureEnabled(MessageID.IDS_FeatureNullableReferenceTypes);

531if (reportIfContextual(SyntaxKind.RecordKeyword, MessageID.IDS_FeatureRecords, ErrorCode.WRN_RecordNamedDisallowed) 532|| reportIfContextual(SyntaxKind.RequiredKeyword, MessageID.IDS_FeatureRequiredMembers, ErrorCode.ERR_RequiredNameDisallowed) 533|| reportIfContextual(SyntaxKind.FileKeyword, MessageID.IDS_FeatureFileTypes, ErrorCode.ERR_FileTypeNameDisallowed) 534|| reportIfContextual(SyntaxKind.ClosedKeyword, MessageID.IDS_FeatureClosedClasses, ErrorCode.ERR_ClosedTypeNameDisallowed) 535|| reportIfContextual(SyntaxKind.ScopedKeyword, MessageID.IDS_FeatureRefFields, ErrorCode.ERR_ScopedTypeNameDisallowed) 536|| reportIfContextual(SyntaxKind.ExtensionKeyword, MessageID.IDS_FeatureExtensions, ErrorCode.ERR_ExtensionTypeNameDisallowed)) 545bool reportIfContextual(SyntaxKind contextualKind, MessageID featureId, ErrorCode error) 1480Binder.CheckFeatureAvailability(t.DeclaringSyntaxReferences[0].GetSyntax(), MessageID.IDS_DefaultInterfaceImplementation, diagnostics, t.GetFirstLocation()); 1948MessageID.IDS_FeatureExtensions.CheckFeatureAvailability(diagnostics, compilation, location); 2407var methodKind = method1.MethodKind == MethodKind.Constructor ? MessageID.IDS_SK_CONSTRUCTOR : MessageID.IDS_SK_METHOD; 4827MessageID.IDS_FeatureExtensionIndexers.CheckFeatureAvailability(diagnostics, this.DeclaringCompilation, member.GetFirstLocation()); 4866return MessageID.IDS_FeatureExtensionIndexers.RequiredVersion() <= languageVersion; 4902MessageID.IDS_FeatureParameterlessStructConstructors.CheckFeatureAvailability(diagnostics, m.DeclaringCompilation, location); 4931MessageID.IDS_FeatureStructFieldInitializers.CheckFeatureAvailability(diagnostics, symbol.DeclaringCompilation, symbol.GetFirstLocation()); 5350if (baseToStringMethod.ContainingModule != this.ContainingModule && !this.DeclaringCompilation.IsFeatureEnabled(MessageID.IDS_FeatureSealedToStringInRecord)) 5353var requiredVersion = MessageID.IDS_FeatureSealedToStringInRecord.RequiredVersion(); 5376MessageID.IDS_FeatureSealedToStringInRecord.CheckFeatureAvailability( 5440Binder.CheckFeatureAvailability(syntax, MessageID.IDS_FeaturePositionalFieldsInRecords, diagnostics);

243MessageID.IDS_FeatureFixedBuffer.CheckFeatureAvailability(diagnostics, modifier); 408Binder.CheckFeatureAvailability(declarator, MessageID.IDS_DefaultInterfaceImplementation, diagnostics, ErrorLocation); 538MessageID.IDS_FeatureRefFields.CheckFeatureAvailability(diagnostics, compilation, typeSyntax.SkipScoped(out _).Location);

1083Binder.CheckFeatureAvailability(declarationSyntax, MessageID.IDS_DefaultInterfaceImplementation, diagnostics, location); 1117Binder.CheckFeatureAvailability(declarationSyntax, MessageID.IDS_FeatureStaticMembersInInterfaces, diagnostics, location);

604MessageID.IDS_FeatureMemberNotNull.CheckFeatureAvailability(diagnostics, arguments.AttributeSyntaxOpt); 609MessageID.IDS_FeatureMemberNotNull.CheckFeatureAvailability(diagnostics, arguments.AttributeSyntaxOpt); 614MessageID.IDS_FeatureModuleInitializers.CheckFeatureAvailability(diagnostics, arguments.AttributeSyntaxOpt); 634MessageID.IDS_FeatureRefStructInterfaces.CheckFeatureAvailability(diagnostics, arguments.AttributeSyntaxOpt); 648MessageID.IDS_FeatureOverloadResolutionPriority.CheckFeatureAvailability(diagnostics, arguments.AttributeSyntaxOpt); 720MessageID.IDS_FeatureObsoleteOnPropertyAccessor.CheckFeatureAvailability(diagnostics, arguments.AttributeSyntaxOpt); 1437diagnostics.Add(ErrorCode.ERR_CannotUseManagedTypeInUnmanagedCallersOnly, syntax.Location, type, (isParam ? MessageID.IDS_Parameter : MessageID.IDS_Return).Localize()); 1564MessageID.IDS_AsyncMethodBuilderOverride.CheckFeatureAvailability(diagnostics, this.DeclaringCompilation, errorLocation);

743bool value = compilation.IsFeatureEnabled(MessageID.IDS_FeatureRefFields) || _assemblySymbol.RuntimeSupportsByRefFields;

109MessageID.IDS_FeatureGenericAttributes.CheckFeatureAvailability(diagnostics, this.DeclaringCompilation, baseLocation); 627Binder.CheckFeatureAvailability(typeSyntax, MessageID.IDS_FeatureRefStructInterfaces, diagnostics);

185MessageID.IDS_FeatureGenerics.CheckFeatureAvailability(diagnostics, tpl.LessThanToken); 201MessageID.IDS_FeatureTypeVariance.CheckFeatureAvailability(diagnostics, tp.VarianceKeyword);

746MessageID.IDS_FeatureUsingTypeAlias.CheckFeatureAvailability(diagnostics, usingDirective, unsafeKeywordLocation); 758if (!compilation.IsFeatureEnabled(MessageID.IDS_FeatureUsingTypeAlias)) 849MessageID.IDS_SK_TYPE_OR_NAMESPACE.Localize());

169syntax.ConstraintClauses[0].WhereKeyword, MessageID.IDS_OverrideWithConstraints, diagnostics); 744var available = MessageID.IDS_FeaturePartialEventsAndConstructors.CheckFeatureAvailability(diagnostics, DeclaringCompilation, ReturnTypeLocation); 875Binder.CheckFeatureAvailability(SyntaxNode, MessageID.IDS_FeatureExtendedPartialMethods, diagnostics, location); 1171MessageID.IDS_FeatureGenerics.CheckFeatureAvailability(diagnostics, syntax.TypeParameterList.LessThanToken);

227Binder.CheckFeatureAvailability(syntax, MessageID.IDS_FeatureInitOnlySetters, diagnostics, location); 245MessageID.IDS_FeaturePropertyAccessorMods.CheckFeatureAvailability(diagnostics, modifiers[0]); 497if (!options.IsFeatureEnabled(MessageID.IDS_FeatureReadOnlyMembers)) 554modifierErrors |= !MessageID.IDS_FeatureUnsafeEvolution.CheckFeatureAvailability(diagnostics, syntax);

53((CSharpParseOptions)syntax.SyntaxTree.Options).IsFeatureEnabled(MessageID.IDS_FeatureFieldKeyword)); 150(hasAutoPropertyGet && hasAutoPropertySet ? MessageID.IDS_FeatureAutoImplementedProperties : MessageID.IDS_FeatureFieldKeyword) : 151(hasAutoPropertyGet ? MessageID.IDS_FeatureReadonlyAutoImplementedProperties : MessageID.IDS_FeatureAutoImplementedProperties), 163MessageID.IDS_FeatureAutoPropertyInitializer.CheckFeatureAvailability(diagnostics, initializer.EqualsToken); 463LanguageVersion requiredVersion = MessageID.IDS_FeaturePartialProperties.RequiredVersion();

322if (!property.DeclaringCompilation.IsFeatureEnabled(MessageID.IDS_FeatureFieldKeyword)) 1642MessageID.IDS_FeatureMemberNotNull.CheckFeatureAvailability(diagnostics, arguments.AttributeSyntaxOpt); 1647MessageID.IDS_FeatureMemberNotNull.CheckFeatureAvailability(diagnostics, arguments.AttributeSyntaxOpt); 1663MessageID.IDS_FeatureRefStructInterfaces.CheckFeatureAvailability(diagnostics, arguments.AttributeSyntaxOpt); 1673MessageID.IDS_FeatureOverloadResolutionPriority.CheckFeatureAvailability(diagnostics, arguments.AttributeSyntaxOpt);

31MessageID.IDS_FeatureCheckedUserDefinedOperators.CheckFeatureAvailability(diagnostics, syntax.CheckedKeyword); 92MessageID.IDS_FeatureStaticAbstractMembersInInterfaces.CheckFeatureAvailability(diagnostics, syntax.ExplicitInterfaceSpecifier);

32MessageID.IDS_FeatureCheckedUserDefinedOperators.CheckFeatureAvailability(diagnostics, syntax.CheckedKeyword); 41MessageID.IDS_FeatureUnsignedRightShift.CheckFeatureAvailability(diagnostics, syntax.OperatorToken); 94MessageID.IDS_FeatureStaticAbstractMembersInInterfaces.CheckFeatureAvailability(diagnostics, syntax.ExplicitInterfaceSpecifier);

60Binder.CheckFeatureAvailability(syntax, MessageID.IDS_FeatureUserDefinedCompoundAssignmentOperators, diagnostics, ((OperatorDeclarationSyntax)syntax).OperatorToken.GetLocation()); 247LanguageVersion requiredVersion = MessageID.IDS_FeatureStaticAbstractMembersInInterfaces.RequiredVersion(); 272Binder.CheckFeatureAvailability(location.SourceTree, MessageID.IDS_DefaultInterfaceImplementation, diagnostics, location); 956Binder.CheckFeatureAvailability(location.SourceTree, MessageID.IDS_FeatureRelaxedShiftOperator, diagnostics, location);

348MessageID.IDS_FeatureGenericAttributes.CheckFeatureAvailability(diagnostics, attributesToBind[i]); 711diagnostics.Add(ErrorCode.WRN_NonECMAFeature, targetOpt.GetLocation(), MessageID.IDS_FeatureModuleAttrLoc);

21return MessageID.IDS_SK_NAMESPACE.Localize(); 23return MessageID.IDS_SK_TYPE.Localize(); 25return MessageID.IDS_SK_TYVAR.Localize(); 27return MessageID.IDS_SK_ARRAY.Localize(); 29return MessageID.IDS_SK_POINTER.Localize(); 31return MessageID.IDS_SK_FUNCTION_POINTER.Localize(); 33return MessageID.IDS_SK_DYNAMIC.Localize(); 35return MessageID.IDS_SK_METHOD.Localize(); 37return MessageID.IDS_SK_PROPERTY.Localize(); 39return MessageID.IDS_SK_EVENT.Localize(); 41return MessageID.IDS_SK_FIELD.Localize(); 45return MessageID.IDS_SK_VARIABLE.Localize(); 47return MessageID.IDS_SK_ALIAS.Localize(); 49return MessageID.IDS_SK_LABEL.Localize(); 53return MessageID.IDS_SK_UNKNOWN.Localize();

182MessageID.IDS_FeaturePrimaryConstructors.CheckFeatureAvailability(diagnostics, attributeDeclarationSyntax, attributeDeclarationSyntax.Target.Identifier.GetLocation());

302new CSharpRequiredLanguageVersion(MessageID.IDS_FeatureAttributesOnBackingFields.RequiredVersion())),

286new CSharpRequiredLanguageVersion(MessageID.IDS_FeatureInferredTupleNames.RequiredVersion())));

1025LanguageVersion requiredVersion = MessageID.IDS_FeatureImplicitImplementationOfNonPublicMembers.RequiredVersion(); 1647var feature = isStatic ? MessageID.IDS_FeatureStaticAbstractMembersInInterfaces : MessageID.IDS_DefaultInterfaceImplementation; 1750LanguageVersion requiredVersion = MessageID.IDS_FeatureStaticAbstractMembersInInterfaces.RequiredVersion(); 1757MessageID.IDS_FeatureStaticAbstractMembersInInterfaces.Localize(), 1996MessageID.IDS_FeatureRefStructInterfaces.CheckFeatureAvailability(diagnostics, implementingSymbol.DeclaringCompilation, applicationSyntaxReference.GetLocation());

179return MessageID.IDS_FeatureVarianceSafetyForStaticInterfaceMembers.RequiredVersion() <= member.DeclaringCompilation.LanguageVersion; 314diagnostics.AddVarianceError(typeParam, context, locationProvider, locationArg, MessageID.IDS_Invariantly); 320diagnostics.AddVarianceError(typeParam, context, locationProvider, locationArg, MessageID.IDS_Covariantly); 326diagnostics.AddVarianceError(typeParam, context, locationProvider, locationArg, MessageID.IDS_Contravariantly); 448MessageID expectedVariance) 451MessageID actualVariance; 455actualVariance = MessageID.IDS_Contravariant; 458actualVariance = MessageID.IDS_Covariant; 478new CSharpRequiredLanguageVersion(MessageID.IDS_FeatureVarianceSafetyForStaticInterfaceMembers.RequiredVersion()));

275MessageID.IDS_FeatureRefLocalsReturns.CheckFeatureAvailability(diagnostics, refType.RefKeyword); 278MessageID.IDS_FeatureReadOnlyReferences.CheckFeatureAvailability(diagnostics, refType.ReadOnlyKeyword); 329MessageID.IDS_FeatureRefLocalsReturns.CheckFeatureAvailability(diagnostics, refExpression.RefKeyword);

85if (compilation.IsFeatureEnabled(MessageID.IDS_FeatureClosedClasses)