type LanguageFeature =

| SingleUnderscorePattern

| WildCardInForLoop

| RelaxWhitespace

| RelaxWhitespace2

| NameOf

| ImplicitYield

| OpenTypeDeclaration

| DotlessFloat32Literal

| PackageManagement

| FromEndSlicing

| FixedIndexSlice3d4d

| AndBang

| ResumableStateMachines

| NullableOptionalInterop

| DefaultInterfaceMemberConsumption

| WitnessPassing

| AdditionalTypeDirectedConversions

| InterfacesWithMultipleGenericInstantiation

| StringInterpolation

| OverloadsForCustomOperations

| ExpandedMeasurables

| NullnessChecking

| StructActivePattern

| PrintfBinaryFormat

| IndexerNotationWithoutDot

| RefCellNotationInformationals

| UseBindingValueDiscard

| UnionIsPropertiesVisible

| NonVariablePatternsToRightOfAsPatterns

| AttributesToRightOfModuleKeyword

| BetterExceptionPrinting

| DelegateTypeNameResolutionFix

| ReallyLongLists

| ErrorOnDeprecatedRequireQualifiedAccess

| RequiredPropertiesSupport

| InitPropertiesSupport

| LowercaseDUWhenRequireQualifiedAccess

| InterfacesWithAbstractStaticMembers

| SelfTypeConstraints

| AccessorFunctionShorthand

| MatchNotAllowedForUnionCaseWithNoData

| CSharpExtensionAttributeNotRequired

| ErrorForNonVirtualMembersOverrides

| WarningWhenInliningMethodImplNoInlineMarkedFunction

| EscapeDotnetFormattableStrings

| ArithmeticInLiterals

| ErrorReportingOnStaticClasses

| TryWithInSeqExpression

| WarningWhenCopyAndUpdateRecordChangesAllFields

| StaticMembersInInterfaces

| NonInlineLiteralsAsPrintfFormat

| NestedCopyAndUpdate

| ExtendedStringInterpolation

| WarningWhenMultipleRecdTypeChoice

| ImprovedImpliedArgumentNames

| DiagnosticForObjInference

| ConstraintIntersectionOnFlexibleTypes

| StaticLetInRecordsDusEmptyTypes

| WarningWhenTailRecAttributeButNonTailRecUsage

| UnmanagedConstraintCsharpInterop

| WhileBang

| ReuseSameFieldsInStructUnions

| ExtendedFixedBindings

| PreferStringGetPinnableReference

| PreferExtensionMethodOverPlainProperty

| WarningIndexedPropertiesGetSetSameType

| WarningWhenTailCallAttrOnNonRec

| BooleanReturningAndReturnTypeDirectedPartialActivePattern

| EnforceAttributeTargets

| LowerInterpolatedStringToConcat

| LowerIntegralRangesToFastLoops

| AllowAccessModifiersToAutoPropertiesGettersAndSetters

| LowerSimpleMappingsInComprehensionsToFastLoops

| ParsedHashDirectiveArgumentNonQuotes

| EmptyBodiedComputationExpressions

| AllowObjectExpressionWithoutOverrides

| DontWarnOnUppercaseIdentifiersInBindingPatterns

| UseTypeSubsumptionCache

| DeprecatePlacesWhereSeqCanBeOmitted

| SupportValueOptionsAsOptionalParameters

| WarnWhenUnitPassedToObjArg

| UseBangBindingValueDiscard

| BetterAnonymousRecordParsing

| ScopedNowarn

| ErrorOnInvalidDeclsInTypeDefinitions

| AllowTypedLetUseAndBang

| ReturnFromFinal

| WarnWhenFunctionValueUsedAsInterpolatedStringArg

| MethodOverloadsCache

| ImplicitDIMCoverage

| PreprocessorElif

| ExceptionFieldSerializationSupport

| ErrorOnMissingSignatureAttribute

| NotNullIfNotNull

| AccessProtectedBaseFieldFromClosure

| ImprovedImpliedArgumentNamesPartTwo

| RecordSpreads

type LanguageVersion(versionText, ?disabledFeaturesArray: LanguageFeature array) =

// When we increment language versions here preview is higher than current RTM version

static let languageVersion46 = 4.6m

static let languageVersion47 = 4.7m

static let languageVersion50 = 5.0m

static let languageVersion60 = 6.0m

static let languageVersion70 = 7.0m

static let languageVersion80 = 8.0m

static let languageVersion90 = 9.0m

static let languageVersion100 = 10.0m

static let languageVersion110 = 11.0m

static let previewVersion = 9999m // Language version when preview specified

static let defaultVersion = languageVersion100 // Language version when default specified

static let latestVersion = defaultVersion // Language version when latest specified

static let latestMajorVersion = defaultVersion // Language version when latestmajor specified

static let validOptions = [| "preview"; "default"; "latest"; "latestmajor" |]

static let languageVersions =

set

[|

languageVersion46

languageVersion47

languageVersion50

languageVersion60

languageVersion70

languageVersion80

languageVersion90

languageVersion100

languageVersion110

|]

static let features =

dict

[

// F# 4.7

LanguageFeature.SingleUnderscorePattern, languageVersion47

LanguageFeature.WildCardInForLoop, languageVersion47

LanguageFeature.RelaxWhitespace, languageVersion47

LanguageFeature.ImplicitYield, languageVersion47

// F# 5.0

LanguageFeature.FixedIndexSlice3d4d, languageVersion50

LanguageFeature.DotlessFloat32Literal, languageVersion50

LanguageFeature.AndBang, languageVersion50

LanguageFeature.NullableOptionalInterop, languageVersion50

LanguageFeature.DefaultInterfaceMemberConsumption, languageVersion50

LanguageFeature.OpenTypeDeclaration, languageVersion50

LanguageFeature.PackageManagement, languageVersion50

LanguageFeature.WitnessPassing, languageVersion50

LanguageFeature.InterfacesWithMultipleGenericInstantiation, languageVersion50

LanguageFeature.NameOf, languageVersion50

LanguageFeature.StringInterpolation, languageVersion50

// F# 6.0

LanguageFeature.AdditionalTypeDirectedConversions, languageVersion60

LanguageFeature.RelaxWhitespace2, languageVersion60

LanguageFeature.OverloadsForCustomOperations, languageVersion60

LanguageFeature.ExpandedMeasurables, languageVersion60

LanguageFeature.ResumableStateMachines, languageVersion60

LanguageFeature.StructActivePattern, languageVersion60

LanguageFeature.PrintfBinaryFormat, languageVersion60

LanguageFeature.IndexerNotationWithoutDot, languageVersion60

LanguageFeature.RefCellNotationInformationals, languageVersion60

LanguageFeature.UseBindingValueDiscard, languageVersion60

LanguageFeature.NonVariablePatternsToRightOfAsPatterns, languageVersion60

LanguageFeature.AttributesToRightOfModuleKeyword, languageVersion60

LanguageFeature.DelegateTypeNameResolutionFix, languageVersion60

// F# 7.0

LanguageFeature.BetterExceptionPrinting, languageVersion70

LanguageFeature.ReallyLongLists, languageVersion70

LanguageFeature.ErrorOnDeprecatedRequireQualifiedAccess, languageVersion70

LanguageFeature.RequiredPropertiesSupport, languageVersion70

LanguageFeature.InitPropertiesSupport, languageVersion70

LanguageFeature.LowercaseDUWhenRequireQualifiedAccess, languageVersion70

LanguageFeature.InterfacesWithAbstractStaticMembers, languageVersion70

LanguageFeature.SelfTypeConstraints, languageVersion70

// F# 8.0

LanguageFeature.AccessorFunctionShorthand, languageVersion80

LanguageFeature.MatchNotAllowedForUnionCaseWithNoData, languageVersion80

LanguageFeature.CSharpExtensionAttributeNotRequired, languageVersion80

LanguageFeature.ErrorForNonVirtualMembersOverrides, languageVersion80

LanguageFeature.WarningWhenInliningMethodImplNoInlineMarkedFunction, languageVersion80

LanguageFeature.EscapeDotnetFormattableStrings, languageVersion80

LanguageFeature.ArithmeticInLiterals, languageVersion80

LanguageFeature.ErrorReportingOnStaticClasses, languageVersion80

LanguageFeature.TryWithInSeqExpression, languageVersion80

LanguageFeature.WarningWhenCopyAndUpdateRecordChangesAllFields, languageVersion80

LanguageFeature.StaticMembersInInterfaces, languageVersion80

LanguageFeature.NonInlineLiteralsAsPrintfFormat, languageVersion80

LanguageFeature.NestedCopyAndUpdate, languageVersion80

LanguageFeature.ExtendedStringInterpolation, languageVersion80

LanguageFeature.WarningWhenMultipleRecdTypeChoice, languageVersion80

LanguageFeature.ImprovedImpliedArgumentNames, languageVersion80

LanguageFeature.DiagnosticForObjInference, languageVersion80

LanguageFeature.WarningWhenTailRecAttributeButNonTailRecUsage, languageVersion80

LanguageFeature.StaticLetInRecordsDusEmptyTypes, languageVersion80

LanguageFeature.ConstraintIntersectionOnFlexibleTypes, languageVersion80

LanguageFeature.WhileBang, languageVersion80

LanguageFeature.ExtendedFixedBindings, languageVersion80

LanguageFeature.PreferStringGetPinnableReference, languageVersion80

// F# 9.0

LanguageFeature.NullnessChecking, languageVersion90

LanguageFeature.ReuseSameFieldsInStructUnions, languageVersion90

LanguageFeature.PreferExtensionMethodOverPlainProperty, languageVersion90

LanguageFeature.WarningIndexedPropertiesGetSetSameType, languageVersion90

LanguageFeature.WarningWhenTailCallAttrOnNonRec, languageVersion90

LanguageFeature.UnionIsPropertiesVisible, languageVersion90

LanguageFeature.BooleanReturningAndReturnTypeDirectedPartialActivePattern, languageVersion90

LanguageFeature.LowerInterpolatedStringToConcat, languageVersion90

LanguageFeature.LowerIntegralRangesToFastLoops, languageVersion90

LanguageFeature.LowerSimpleMappingsInComprehensionsToFastLoops, languageVersion90

LanguageFeature.ParsedHashDirectiveArgumentNonQuotes, languageVersion90

LanguageFeature.EmptyBodiedComputationExpressions, languageVersion90

// F# 10.0

LanguageFeature.EnforceAttributeTargets, languageVersion100

LanguageFeature.UseTypeSubsumptionCache, languageVersion100

LanguageFeature.AllowObjectExpressionWithoutOverrides, languageVersion100

LanguageFeature.DontWarnOnUppercaseIdentifiersInBindingPatterns, languageVersion100

LanguageFeature.DeprecatePlacesWhereSeqCanBeOmitted, languageVersion100

LanguageFeature.SupportValueOptionsAsOptionalParameters, languageVersion100

LanguageFeature.WarnWhenUnitPassedToObjArg, languageVersion100

LanguageFeature.UseBangBindingValueDiscard, languageVersion100

LanguageFeature.BetterAnonymousRecordParsing, languageVersion100

LanguageFeature.ScopedNowarn, languageVersion100

LanguageFeature.AllowTypedLetUseAndBang, languageVersion100

LanguageFeature.UnmanagedConstraintCsharpInterop, languageVersion100

LanguageFeature.AllowAccessModifiersToAutoPropertiesGettersAndSetters, languageVersion100

LanguageFeature.ReturnFromFinal, languageVersion100

LanguageFeature.ErrorOnInvalidDeclsInTypeDefinitions, languageVersion100

// F# 11.0

// Put stabilized features here for F# 11.0 previews via .NET SDK preview channels

LanguageFeature.WarnWhenFunctionValueUsedAsInterpolatedStringArg, languageVersion110

LanguageFeature.PreprocessorElif, languageVersion110

LanguageFeature.ExceptionFieldSerializationSupport, languageVersion110

LanguageFeature.NotNullIfNotNull, languageVersion110

LanguageFeature.ImprovedImpliedArgumentNamesPartTwo, languageVersion110

// Difference between languageVersion110 and preview - 11.0 gets turned on automatically by picking a preview .NET 11 SDK

// previewVersion is only when "preview" is specified explicitly in project files and users also need a preview SDK

// F# preview (still preview in 10.0)

LanguageFeature.FromEndSlicing, previewVersion // Unfinished features --- needs work

LanguageFeature.MethodOverloadsCache, previewVersion // Performance optimization for overload resolution

LanguageFeature.ImplicitDIMCoverage, languageVersion110

LanguageFeature.ErrorOnMissingSignatureAttribute, previewVersion // Opt-in: turn FS3888 from warning into error

LanguageFeature.AccessProtectedBaseFieldFromClosure, previewVersion // #5302: read a protected base field from a closure

LanguageFeature.RecordSpreads, previewVersion

]

static let defaultLanguageVersion = LanguageVersion("default")

static let getVersionFromString (version: string) =

match version.ToUpperInvariant() with

| "?" -> 0m

| "PREVIEW" -> previewVersion

| "DEFAULT" -> defaultVersion

| "LATEST" -> latestVersion

| "LATESTMAJOR" -> latestMajorVersion

| "4.6" -> languageVersion46

| "4.7" -> languageVersion47

| "5.0"

| "5" -> languageVersion50

| "6.0"

| "6" -> languageVersion60

| "7.0"

| "7" -> languageVersion70

| "8.0"

| "8" -> languageVersion80

| "9.0"

| "9" -> languageVersion90

| "10.0"

| "10" -> languageVersion100

| "11.0"

| "11" -> languageVersion110

| _ -> 0m

let specified = getVersionFromString versionText

static let versionToString v =

if v = previewVersion then "'PREVIEW'" else string v

let specifiedString = versionToString specified

let disabledFeatures: LanguageFeature array = defaultArg disabledFeaturesArray [||]

/// Get the disabled features

member _.DisabledFeatures = disabledFeatures

/// Check if this feature is supported by the selected langversion

member _.SupportsFeature featureId =

if Array.contains featureId disabledFeatures then

false

else

match features.TryGetValue featureId with

| true, v -> v <= specified

| false, _ -> false

/// Create a new LanguageVersion with updated disabled features

member _.WithDisabledFeatures(disabled: LanguageFeature array) = LanguageVersion(versionText, disabled)

/// Has preview been explicitly specified

member _.IsExplicitlySpecifiedAs50OrBefore() =

let v = getVersionFromString versionText

v <> 0.0m && v <= 5.0m

/// Has preview been explicitly specified

member _.IsPreviewEnabled = specified = previewVersion

/// Is the selected LanguageVersion valid

static member ContainsVersion version =

let langVersion = getVersionFromString version

langVersion <> 0m && languageVersions.Contains langVersion

/// Is the selected LanguageVersion currently supported

static member IsVersionSupported version =

let langVersion = getVersionFromString version

langVersion >= languageVersion80

|| System.Environment.GetEnvironmentVariable("SKIP_VERSION_SUPPORTED_CHECK") = "1"

/// Get a list of valid strings for help text

static member ValidOptions = validOptions

/// Get a list of valid versions for help text

static member ValidVersions =

[|

for v in languageVersions |> Seq.sort -> sprintf "%M%s" v (if v = defaultVersion then " (Default)" else "")

|]

/// Get the text used to specify the version

member _.VersionText = versionText

/// Get the specified LanguageVersion

member _.SpecifiedVersion = specified

/// Get the specified LanguageVersion as a string

member _.SpecifiedVersionString = specifiedString

/// Get a string name for the given feature.

static member GetFeatureString feature =

match feature with

| LanguageFeature.SingleUnderscorePattern -> FSComp.SR.featureSingleUnderscorePattern ()

| LanguageFeature.WildCardInForLoop -> FSComp.SR.featureWildCardInForLoop ()

| LanguageFeature.RelaxWhitespace -> FSComp.SR.featureRelaxWhitespace ()

| LanguageFeature.RelaxWhitespace2 -> FSComp.SR.featureRelaxWhitespace2 ()

| LanguageFeature.NameOf -> FSComp.SR.featureNameOf ()

| LanguageFeature.ImplicitYield -> FSComp.SR.featureImplicitYield ()

| LanguageFeature.OpenTypeDeclaration -> FSComp.SR.featureOpenTypeDeclaration ()

| LanguageFeature.DotlessFloat32Literal -> FSComp.SR.featureDotlessFloat32Literal ()

| LanguageFeature.PackageManagement -> FSComp.SR.featurePackageManagement ()

| LanguageFeature.FromEndSlicing -> FSComp.SR.featureFromEndSlicing ()

| LanguageFeature.FixedIndexSlice3d4d -> FSComp.SR.featureFixedIndexSlice3d4d ()

| LanguageFeature.AndBang -> FSComp.SR.featureAndBang ()

| LanguageFeature.NullnessChecking -> FSComp.SR.featureNullnessChecking ()

| LanguageFeature.ResumableStateMachines -> FSComp.SR.featureResumableStateMachines ()

| LanguageFeature.NullableOptionalInterop -> FSComp.SR.featureNullableOptionalInterop ()

| LanguageFeature.DefaultInterfaceMemberConsumption -> FSComp.SR.featureDefaultInterfaceMemberConsumption ()

| LanguageFeature.WitnessPassing -> FSComp.SR.featureWitnessPassing ()

| LanguageFeature.AdditionalTypeDirectedConversions -> FSComp.SR.featureAdditionalImplicitConversions ()

| LanguageFeature.InterfacesWithMultipleGenericInstantiation -> FSComp.SR.featureInterfacesWithMultipleGenericInstantiation ()

| LanguageFeature.StringInterpolation -> FSComp.SR.featureStringInterpolation ()

| LanguageFeature.OverloadsForCustomOperations -> FSComp.SR.featureOverloadsForCustomOperations ()

| LanguageFeature.ExpandedMeasurables -> FSComp.SR.featureExpandedMeasurables ()

| LanguageFeature.StructActivePattern -> FSComp.SR.featureStructActivePattern ()

| LanguageFeature.PrintfBinaryFormat -> FSComp.SR.featurePrintfBinaryFormat ()

| LanguageFeature.IndexerNotationWithoutDot -> FSComp.SR.featureIndexerNotationWithoutDot ()

| LanguageFeature.RefCellNotationInformationals -> FSComp.SR.featureRefCellNotationInformationals ()

| LanguageFeature.UseBindingValueDiscard -> FSComp.SR.featureDiscardUseValue ()

| LanguageFeature.UnionIsPropertiesVisible -> FSComp.SR.featureUnionIsPropertiesVisible ()

| LanguageFeature.NonVariablePatternsToRightOfAsPatterns -> FSComp.SR.featureNonVariablePatternsToRightOfAsPatterns ()

| LanguageFeature.AttributesToRightOfModuleKeyword -> FSComp.SR.featureAttributesToRightOfModuleKeyword ()

| LanguageFeature.BetterExceptionPrinting -> FSComp.SR.featureBetterExceptionPrinting ()

| LanguageFeature.DelegateTypeNameResolutionFix -> FSComp.SR.featureDelegateTypeNameResolutionFix ()

| LanguageFeature.ReallyLongLists -> FSComp.SR.featureReallyLongList ()

| LanguageFeature.ErrorOnDeprecatedRequireQualifiedAccess -> FSComp.SR.featureErrorOnDeprecatedRequireQualifiedAccess ()

| LanguageFeature.RequiredPropertiesSupport -> FSComp.SR.featureRequiredProperties ()

| LanguageFeature.InitPropertiesSupport -> FSComp.SR.featureInitProperties ()

| LanguageFeature.LowercaseDUWhenRequireQualifiedAccess -> FSComp.SR.featureLowercaseDUWhenRequireQualifiedAccess ()

| LanguageFeature.InterfacesWithAbstractStaticMembers -> FSComp.SR.featureInterfacesWithAbstractStaticMembers ()

| LanguageFeature.SelfTypeConstraints -> FSComp.SR.featureSelfTypeConstraints ()

| LanguageFeature.AccessorFunctionShorthand -> FSComp.SR.featureAccessorFunctionShorthand ()

| LanguageFeature.MatchNotAllowedForUnionCaseWithNoData -> FSComp.SR.featureMatchNotAllowedForUnionCaseWithNoData ()

| LanguageFeature.CSharpExtensionAttributeNotRequired -> FSComp.SR.featureCSharpExtensionAttributeNotRequired ()

| LanguageFeature.ErrorForNonVirtualMembersOverrides -> FSComp.SR.featureErrorForNonVirtualMembersOverrides ()

| LanguageFeature.WarningWhenInliningMethodImplNoInlineMarkedFunction ->

FSComp.SR.featureWarningWhenInliningMethodImplNoInlineMarkedFunction ()

| LanguageFeature.EscapeDotnetFormattableStrings -> FSComp.SR.featureEscapeBracesInFormattableString ()

| LanguageFeature.ArithmeticInLiterals -> FSComp.SR.featureArithmeticInLiterals ()

| LanguageFeature.ErrorReportingOnStaticClasses -> FSComp.SR.featureErrorReportingOnStaticClasses ()

| LanguageFeature.TryWithInSeqExpression -> FSComp.SR.featureTryWithInSeqExpressions ()

| LanguageFeature.WarningWhenCopyAndUpdateRecordChangesAllFields ->

FSComp.SR.featureWarningWhenCopyAndUpdateRecordChangesAllFields ()

| LanguageFeature.StaticMembersInInterfaces -> FSComp.SR.featureStaticMembersInInterfaces ()

| LanguageFeature.NonInlineLiteralsAsPrintfFormat -> FSComp.SR.featureNonInlineLiteralsAsPrintfFormat ()

| LanguageFeature.NestedCopyAndUpdate -> FSComp.SR.featureNestedCopyAndUpdate ()

| LanguageFeature.ExtendedStringInterpolation -> FSComp.SR.featureExtendedStringInterpolation ()

| LanguageFeature.WarningWhenMultipleRecdTypeChoice -> FSComp.SR.featureWarningWhenMultipleRecdTypeChoice ()

| LanguageFeature.ImprovedImpliedArgumentNames -> FSComp.SR.featureImprovedImpliedArgumentNames ()

| LanguageFeature.DiagnosticForObjInference -> FSComp.SR.featureInformationalObjInferenceDiagnostic ()

| LanguageFeature.StaticLetInRecordsDusEmptyTypes -> FSComp.SR.featureStaticLetInRecordsDusEmptyTypes ()

| LanguageFeature.ConstraintIntersectionOnFlexibleTypes -> FSComp.SR.featureConstraintIntersectionOnFlexibleTypes ()

| LanguageFeature.WarningWhenTailRecAttributeButNonTailRecUsage -> FSComp.SR.featureChkNotTailRecursive ()

| LanguageFeature.UnmanagedConstraintCsharpInterop -> FSComp.SR.featureUnmanagedConstraintCsharpInterop ()

| LanguageFeature.WhileBang -> FSComp.SR.featureWhileBang ()

| LanguageFeature.ReuseSameFieldsInStructUnions -> FSComp.SR.featureReuseSameFieldsInStructUnions ()

| LanguageFeature.ExtendedFixedBindings -> FSComp.SR.featureExtendedFixedBindings ()

| LanguageFeature.PreferStringGetPinnableReference -> FSComp.SR.featurePreferStringGetPinnableReference ()

| LanguageFeature.PreferExtensionMethodOverPlainProperty -> FSComp.SR.featurePreferExtensionMethodOverPlainProperty ()

| LanguageFeature.WarningIndexedPropertiesGetSetSameType -> FSComp.SR.featureWarningIndexedPropertiesGetSetSameType ()

| LanguageFeature.WarningWhenTailCallAttrOnNonRec -> FSComp.SR.featureChkTailCallAttrOnNonRec ()

| LanguageFeature.BooleanReturningAndReturnTypeDirectedPartialActivePattern ->

FSComp.SR.featureBooleanReturningAndReturnTypeDirectedPartialActivePattern ()

| LanguageFeature.EnforceAttributeTargets -> FSComp.SR.featureEnforceAttributeTargets ()

| LanguageFeature.LowerInterpolatedStringToConcat -> FSComp.SR.featureLowerInterpolatedStringToConcat ()

| LanguageFeature.LowerIntegralRangesToFastLoops -> FSComp.SR.featureLowerIntegralRangesToFastLoops ()

| LanguageFeature.AllowAccessModifiersToAutoPropertiesGettersAndSetters ->

FSComp.SR.featureAllowAccessModifiersToAutoPropertiesGettersAndSetters ()

| LanguageFeature.LowerSimpleMappingsInComprehensionsToFastLoops ->

FSComp.SR.featureLowerSimpleMappingsInComprehensionsToFastLoops ()

| LanguageFeature.ParsedHashDirectiveArgumentNonQuotes -> FSComp.SR.featureParsedHashDirectiveArgumentNonString ()

| LanguageFeature.EmptyBodiedComputationExpressions -> FSComp.SR.featureEmptyBodiedComputationExpressions ()

| LanguageFeature.AllowObjectExpressionWithoutOverrides -> FSComp.SR.featureAllowObjectExpressionWithoutOverrides ()

| LanguageFeature.DontWarnOnUppercaseIdentifiersInBindingPatterns ->

FSComp.SR.featureDontWarnOnUppercaseIdentifiersInBindingPatterns ()

| LanguageFeature.UseTypeSubsumptionCache -> FSComp.SR.featureUseTypeSubsumptionCache ()

| LanguageFeature.DeprecatePlacesWhereSeqCanBeOmitted -> FSComp.SR.featureDeprecatePlacesWhereSeqCanBeOmitted ()

| LanguageFeature.SupportValueOptionsAsOptionalParameters -> FSComp.SR.featureSupportValueOptionsAsOptionalParameters ()

| LanguageFeature.WarnWhenUnitPassedToObjArg -> FSComp.SR.featureSupportWarnWhenUnitPassedToObjArg ()

| LanguageFeature.UseBangBindingValueDiscard -> FSComp.SR.featureUseBangBindingValueDiscard ()

| LanguageFeature.BetterAnonymousRecordParsing -> FSComp.SR.featureBetterAnonymousRecordParsing ()

| LanguageFeature.ScopedNowarn -> FSComp.SR.featureScopedNowarn ()

| LanguageFeature.ErrorOnInvalidDeclsInTypeDefinitions -> FSComp.SR.featureErrorOnInvalidDeclsInTypeDefinitions ()

| LanguageFeature.AllowTypedLetUseAndBang -> FSComp.SR.featureAllowLetOrUseBangTypeAnnotationWithoutParens ()

| LanguageFeature.ReturnFromFinal -> FSComp.SR.featureReturnFromFinal ()

| LanguageFeature.WarnWhenFunctionValueUsedAsInterpolatedStringArg ->

FSComp.SR.featureWarnWhenFunctionValueUsedAsInterpolatedStringArg ()

| LanguageFeature.MethodOverloadsCache -> FSComp.SR.featureMethodOverloadsCache ()

| LanguageFeature.ImplicitDIMCoverage -> FSComp.SR.featureImplicitDIMCoverage ()

| LanguageFeature.PreprocessorElif -> FSComp.SR.featurePreprocessorElif ()

| LanguageFeature.ExceptionFieldSerializationSupport -> FSComp.SR.featureExceptionFieldSerializationSupport ()

| LanguageFeature.ErrorOnMissingSignatureAttribute -> FSComp.SR.featureErrorOnMissingSignatureAttribute ()

| LanguageFeature.NotNullIfNotNull -> FSComp.SR.featureNotNullIfNotNull ()

| LanguageFeature.AccessProtectedBaseFieldFromClosure -> FSComp.SR.featureAccessProtectedBaseFieldFromClosure ()

| LanguageFeature.ImprovedImpliedArgumentNamesPartTwo -> FSComp.SR.featureImprovedImpliedArgumentNamesPartTwo ()

| LanguageFeature.RecordSpreads -> FSComp.SR.featureRecordSpreads ()

/// Get a version string associated with the given feature.

static member GetFeatureVersionString feature =

match features.TryGetValue feature with

| true, v -> versionToString v

| _ -> invalidArg "feature" "Internal error: Unable to find feature."

/// Try to parse a feature name string to a LanguageFeature option using reflection

static member TryParseFeature(featureName: string) =

let normalized = featureName.Trim()

let bindingFlags =

System.Reflection.BindingFlags.Public

||| System.Reflection.BindingFlags.NonPublic

Microsoft.FSharp.Reflection.FSharpType.GetUnionCases(typeof<LanguageFeature>, bindingFlags)

|> Array.tryFind (fun case -> System.String.Equals(case.Name, normalized, System.StringComparison.OrdinalIgnoreCase))

|> Option.bind (fun case ->

let union =

Microsoft.FSharp.Reflection.FSharpValue.MakeUnion(case, [||], bindingFlags)

match box union with

| null -> None

| obj -> Some(obj :?> LanguageFeature))

override x.Equals(yobj: obj) =

match yobj with

| :? LanguageVersion as y ->

x.SpecifiedVersion = y.SpecifiedVersion

&& x.DisabledFeatures.Length = y.DisabledFeatures.Length

&& (x.DisabledFeatures, y.DisabledFeatures) ||> Array.forall2 (=)

| _ -> false

override x.GetHashCode() =

let mutable h = hash x.SpecifiedVersion

for f in x.DisabledFeatures do

h <- h ^^^ hash f

h

static member Default = defaultLanguageVersion