| O | GHC.Base | 
| object | Text.XHtml.Strict, Text.XHtml.Frameset, Text.XHtml.Transitional, Text.XHtml | 
| ObjectiveC | Distribution.Simple.CCompiler | 
| ObjectiveCPlusPlus | Distribution.Simple.CCompiler | 
| objectName | GHC.ExecutionStack.Internal, GHC.ExecutionStack | 
| objExtension | Distribution.Simple.BuildPaths | 
| OCaml_LGPL_linking_exception | Distribution.SPDX.LicenseExceptionId, Distribution.SPDX | 
| OccName |  | 
| 1 (Data Constructor) | Language.Haskell.TH.Syntax | 
| 2 (Type/Class) | Language.Haskell.TH.Syntax | 
| occString | Language.Haskell.TH.Syntax | 
| OCCT_exception_1_0 | Distribution.SPDX.LicenseExceptionId, Distribution.SPDX | 
| OCCT_PL | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OCLC_2_0 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| octal | Text.Parsec.Token, Text.ParserCombinators.Parsec.Token | 
| octDigit |  | 
| 1 (Function) | Distribution.Compat.CharParsing | 
| 2 (Function) | Text.Parsec.Char, Text.Parsec, Text.ParserCombinators.Parsec.Char, Text.ParserCombinators.Parsec | 
| ODbL_1_0 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| ODC_By_1_0 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| odd |  | 
| 1 (Function) | Distribution.Compat.Prelude.Internal | 
| 2 (Function) | GHC.Real, Prelude | 
| 3 (Function) | System.Directory.Internal.Prelude | 
| OddParity | System.Posix.Terminal.ByteString, System.Posix.Terminal, System.Posix.ByteString, System.Posix | 
| OFL_1_0 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OFL_1_0_no_RFN | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OFL_1_0_RFN | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OFL_1_1 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OFL_1_1_no_RFN | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OFL_1_1_RFN | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OGC_1_0 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OGL_Canada_2_0 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OGL_UK_1_0 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OGL_UK_2_0 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OGL_UK_3_0 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OGTSL | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| Ok | Text.Parsec.Prim, Text.Parsec | 
| okSymChar | GHC.Lexeme | 
| OLDAP_1_1 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OLDAP_1_2 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OLDAP_1_3 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OLDAP_1_4 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OLDAP_2_0 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OLDAP_2_0_1 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OLDAP_2_1 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OLDAP_2_2 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OLDAP_2_2_1 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OLDAP_2_2_2 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OLDAP_2_3 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OLDAP_2_4 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OLDAP_2_5 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OLDAP_2_6 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OLDAP_2_7 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OLDAP_2_8 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| oldExtensions |  | 
| 1 (Function) | Distribution.Types.BuildInfo.Lens, Distribution.Types.Lens | 
| 2 (Function) | Distribution.Types.BuildInfo, Distribution.PackageDescription | 
| oldGenFactor | GHC.RTS.Flags | 
| olist | Text.XHtml.Strict, Text.XHtml.Frameset, Text.XHtml.Transitional, Text.XHtml | 
| olive | Text.XHtml.Transitional, Text.XHtml | 
| OML | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| on |  | 
| 1 (Function) | Distribution.Compat.Prelude.Internal | 
| 2 (Function) | Data.Function | 
| 3 (Function) | System.Directory.Internal.Prelude | 
| OnDecodeError | Data.Text.Encoding.Error | 
| One |  | 
| 1 (Data Constructor) | Data.Sequence.Internal | 
| 2 (Data Constructor) | GHC.Types | 
| oneBigNat | GHC.Integer.GMP.Internals | 
| OneComponentRequestedSpec | Distribution.Types.ComponentRequestedSpec | 
| OneLineGCStats | GHC.RTS.Flags | 
| OneLineMode | Text.PrettyPrint.Annotated.HughesPJ, Text.PrettyPrint.Annotated, Text.PrettyPrint.Annotated.HughesPJClass, Text.PrettyPrint.HughesPJ, Text.PrettyPrint, Text.PrettyPrint.HughesPJClass | 
| oneName | Language.Haskell.TH.Syntax | 
| OnEncodeError | Data.Text.Encoding.Error | 
| oneOf |  | 
| 1 (Function) | Distribution.Compat.CharParsing | 
| 2 (Function) | Text.Parsec.Char, Text.Parsec, Text.ParserCombinators.Parsec.Char, Text.ParserCombinators.Parsec | 
| OnError | Data.Text.Encoding.Error | 
| onError | Control.Monad.Catch, Control.Monad.Catch.Pure | 
| OneShot | GHC.Event | 
| oneShot |  | 
| 1 (Function) | GHC.Base, GHC.Exts | 
| 2 (Function) | GHC.Magic | 
| onException |  | 
| 1 (Function) | Control.Exception, Control.Exception.Base | 
| 2 (Function) | GHC.IO | 
| 3 (Function) | System.Directory.Internal.Prelude | 
| 4 (Function) | Control.Monad.Catch, Control.Monad.Catch.Pure | 
| Op |  | 
| 1 (Data Constructor) | Data.Functor.Contravariant | 
| 2 (Type/Class) | Data.Functor.Contravariant | 
| Opaque | GHC.Base | 
| openBinaryFile |  | 
| 1 (Function) | System.IO, GHC.IO.StdHandles | 
| 2 (Function) | GHC.IO.Handle.FD | 
| openBinaryTempFile |  | 
| 1 (Function) | System.IO | 
| 2 (Function) | System.Directory.Internal.Prelude | 
| openBinaryTempFileWithDefaultPermissions | System.IO | 
| OpenBrace | Distribution.Fields.Lexer | 
| OpenBSD | Distribution.System | 
| openDirStream |  | 
| 1 (Function) | System.Posix.Directory, System.Posix | 
| 2 (Function) | System.Posix.Directory.ByteString, System.Posix.ByteString | 
| openEndedPipe | System.Posix.Signals, System.Posix.Signals.Exts, System.Posix.ByteString, System.Posix | 
| OpenExtHandle | System.Process.Internals | 
| openFd |  | 
| 1 (Function) | System.Posix.IO, System.Posix | 
| 2 (Function) | System.Posix.IO.ByteString, System.Posix.ByteString | 
| openFile |  | 
| 1 (Function) | System.IO, GHC.IO.StdHandles | 
| 2 (Function) | GHC.IO.Handle.FD | 
| 3 (Function) | GHC.IO.FD | 
| openFileBlocking |  | 
| 1 (Function) | GHC.IO.StdHandles | 
| 2 (Function) | GHC.IO.Handle.FD | 
| OpenFileFlags |  | 
| 1 (Data Constructor) | System.Posix.IO.ByteString, System.Posix.IO, System.Posix.ByteString, System.Posix | 
| 2 (Type/Class) | System.Posix.IO.ByteString, System.Posix.IO, System.Posix.ByteString, System.Posix | 
| OpenFileLimit | System.Posix.Unistd, System.Posix.ByteString, System.Posix | 
| OpenHandle | System.Process.Internals | 
| OpenJDK_assembly_exception_1_0 | Distribution.SPDX.LicenseExceptionId, Distribution.SPDX | 
| OpenMode | System.Posix.IO.ByteString, System.Posix.IO, System.Posix.ByteString, System.Posix | 
| OpenModule |  | 
| 1 (Data Constructor) | Distribution.Backpack | 
| 2 (Type/Class) | Distribution.Backpack | 
| openModuleFreeHoles | Distribution.Backpack | 
| OpenModuleSubst | Distribution.Backpack | 
| openModuleSubstFreeHoles | Distribution.Backpack | 
| OpenModuleVar | Distribution.Backpack | 
| openPseudoTerminal |  | 
| 1 (Function) | System.Posix.Terminal, System.Posix | 
| 2 (Function) | System.Posix.Terminal.ByteString, System.Posix.ByteString | 
| OpenPunctuation | GHC.Unicode, Data.Char | 
| OpenSemFlags |  | 
| 1 (Data Constructor) | System.Posix.Semaphore, System.Posix.ByteString, System.Posix | 
| 2 (Type/Class) | System.Posix.Semaphore, System.Posix.ByteString, System.Posix | 
| OpenSSL | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| openTempFile | System.IO | 
| openTempFileWithDefaultPermissions | System.IO | 
| openTextEncoding | GHC.IO.Handle.Internals | 
| OpenTypeFamilyD | Language.Haskell.TH.Syntax, Language.Haskell.TH | 
| openTypeFamilyD |  | 
| 1 (Function) | Language.Haskell.TH.Lib, Language.Haskell.TH | 
| 2 (Function) | Language.Haskell.TH.Lib.Internal | 
| OpenUnitId | Distribution.Backpack | 
| openUnitIdFreeHoles | Distribution.Backpack | 
| Openvpn_openssl_exception | Distribution.SPDX.LicenseExceptionId, Distribution.SPDX | 
| Operator |  | 
| 1 (Type/Class) | Text.ParserCombinators.Parsec.Expr | 
| 2 (Type/Class) | Text.Parsec.Expr | 
| operator | Text.Parsec.Token, Text.ParserCombinators.Parsec.Token | 
| OperatorTable |  | 
| 1 (Type/Class) | Text.ParserCombinators.Parsec.Expr | 
| 2 (Type/Class) | Text.Parsec.Expr | 
| opLetter | Text.Parsec.Token, Text.ParserCombinators.Parsec.Language, Text.ParserCombinators.Parsec.Token | 
| OPL_1_0 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| opPrec | Language.Haskell.TH.Ppr | 
| opStart | Text.Parsec.Token, Text.ParserCombinators.Parsec.Language, Text.ParserCombinators.Parsec.Token | 
| OptArg |  | 
| 1 (Data Constructor) | Distribution.Simple.Command | 
| 2 (Data Constructor) | System.Console.GetOpt | 
| optArg | Distribution.Simple.Command | 
| optArg' | Distribution.Simple.Command | 
| OptDescr |  | 
| 1 (Type/Class) | Distribution.Simple.Command | 
| 2 (Type/Class) | System.Console.GetOpt | 
| OptFlags | Distribution.Simple.Command | 
| optgroup | Text.XHtml.Strict, Text.XHtml.Frameset, Text.XHtml.Transitional, Text.XHtml | 
| OptimisationLevel | Distribution.Simple.Compiler, Distribution.Simple | 
| Option |  | 
| 1 (Data Constructor) | Data.Semigroup | 
| 2 (Type/Class) | Data.Semigroup | 
| 3 (Data Constructor) | System.Console.GetOpt | 
| option |  | 
| 1 (Function) | Distribution.Simple.Command | 
| 2 (Function) | Distribution.Compat.Parsing, Distribution.Compat.CharParsing | 
| 3 (Function) | Data.Semigroup | 
| 4 (Function) | Text.ParserCombinators.ReadP | 
| 5 (Function) | Text.Parsec.Combinator, Text.Parsec, Text.ParserCombinators.Parsec.Combinator, Text.ParserCombinators.Parsec | 
| 6 (Function) | Text.XHtml.Strict, Text.XHtml.Frameset, Text.XHtml.Transitional, Text.XHtml | 
| Option' |  | 
| 1 (Data Constructor) | Distribution.Compat.Semigroup | 
| 2 (Type/Class) | Distribution.Compat.Semigroup | 
| optional |  | 
| 1 (Function) | Distribution.Compat.Parsing, Distribution.Compat.CharParsing | 
| 2 (Function) | Control.Applicative | 
| 3 (Function) | Text.ParserCombinators.ReadP | 
| 4 (Function) | Text.Parsec.Combinator, Text.Parsec, Text.ParserCombinators.Parsec.Combinator, Text.ParserCombinators.Parsec | 
| optionalField | Distribution.FieldGrammar.Class, Distribution.FieldGrammar | 
| optionalFieldAla | Distribution.FieldGrammar.Class, Distribution.FieldGrammar | 
| optionalFieldDef | Distribution.FieldGrammar.Class, Distribution.FieldGrammar | 
| optionalFieldDefAla | Distribution.FieldGrammar.Class, Distribution.FieldGrammar | 
| OptionBool | Distribution.TestSuite | 
| optionDefault | Distribution.TestSuite | 
| OptionDescr |  | 
| 1 (Data Constructor) | Distribution.TestSuite | 
| 2 (Type/Class) | Distribution.TestSuite | 
| optionDescr | Distribution.Simple.Command | 
| optionDescription | Distribution.TestSuite | 
| optionDistPref | Distribution.Simple.Setup | 
| OptionEnum | Distribution.TestSuite | 
| OptionField |  | 
| 1 (Data Constructor) | Distribution.Simple.Command | 
| 2 (Type/Class) | Distribution.Simple.Command | 
| OptionFile | Distribution.TestSuite | 
| optionFileExtensions | Distribution.TestSuite | 
| optionFileIsDir | Distribution.TestSuite | 
| optionFileMustExist | Distribution.TestSuite | 
| optionMaybe | Text.Parsec.Combinator, Text.Parsec, Text.ParserCombinators.Parsec.Combinator, Text.ParserCombinators.Parsec | 
| optionName |  | 
| 1 (Function) | Distribution.Simple.Command | 
| 2 (Function) | Distribution.TestSuite | 
| OptionNumber | Distribution.TestSuite | 
| optionNumberBounds | Distribution.TestSuite | 
| optionNumberIsInt | Distribution.TestSuite | 
| optionNumJobs | Distribution.Simple.Setup | 
| OptionRngSeed | Distribution.TestSuite | 
| Options | Distribution.TestSuite | 
| options |  | 
| 1 (Function) | Distribution.Types.BuildInfo.Lens, Distribution.Types.Lens | 
| 2 (Function) | Distribution.Types.BuildInfo, Distribution.PackageDescription | 
| 3 (Function) | Distribution.TestSuite | 
| OptionSet | Distribution.TestSuite | 
| OptionString | Distribution.TestSuite | 
| optionStringMultiline | Distribution.TestSuite | 
| OptionType | Distribution.TestSuite | 
| optionType | Distribution.TestSuite | 
| optionVerbosity | Distribution.Simple.Setup | 
| optKeepTempFiles | Distribution.Simple.Utils | 
| or |  | 
| 1 (Function) | Distribution.Compat.Prelude.Internal | 
| 2 (Function) | Data.List, Data.Foldable, Prelude | 
| 3 (Function) | GHC.List, GHC.OldList | 
| 4 (Function) | System.Directory.Internal.Prelude | 
| or# |  | 
| 1 (Function) | GHC.Base, GHC.Exts | 
| 2 (Function) | GHC.PrimopWrappers | 
| 3 (Function) | GHC.Prim | 
| orBigNat | GHC.Integer.GMP.Internals | 
| Ord |  | 
| 1 (Type/Class) | Distribution.Compat.Prelude.Internal | 
| 2 (Type/Class) | GHC.Base, Data.Ord, Prelude | 
| 3 (Type/Class) | System.Directory.Internal.Prelude | 
| 4 (Type/Class) | GHC.Classes | 
| ord |  | 
| 1 (Function) | Distribution.Compat.Prelude.Internal | 
| 2 (Function) | GHC.Base, Data.Char | 
| 3 (Function) | Data.Text.Internal.Unsafe.Char | 
| ord# |  | 
| 1 (Function) | GHC.Base, GHC.Exts | 
| 2 (Function) | GHC.PrimopWrappers | 
| 3 (Function) | GHC.Prim | 
| Ord1 | Data.Functor.Classes | 
| Ord2 | Data.Functor.Classes | 
| ord2 | Data.Text.Internal.Encoding.Utf8 | 
| ord3 | Data.Text.Internal.Encoding.Utf8 | 
| ord4 | Data.Text.Internal.Encoding.Utf8 | 
| ordered | Data.Map.Internal.Debug | 
| Ordering |  | 
| 1 (Type/Class) | Distribution.Compat.Prelude.Internal | 
| 2 (Type/Class) | GHC.Base, Data.Ord, Prelude | 
| 3 (Type/Class) | System.Directory.Internal.Prelude | 
| 4 (Type/Class) | GHC.Types | 
| ordinalDateFormat | Data.Time.Format.ISO8601 | 
| Ordinary | Distribution.Simple.InstallDirs.Internal | 
| ordList | Text.XHtml.Strict, Text.XHtml.Frameset, Text.XHtml.Transitional, Text.XHtml | 
| ordNub | Distribution.Utils.Generic, Distribution.Simple.Utils | 
| ordNubBy | Distribution.Utils.Generic, Distribution.Simple.Utils | 
| ordNubRight | Distribution.Utils.Generic, Distribution.Simple.Utils | 
| OrEarlierVersion | Distribution.Types.VersionRange.Internal | 
| orEarlierVersion | Distribution.Types.VersionRange.Internal, Distribution.Types.VersionRange, Distribution.Version, Distribution.Simple | 
| OrEarlierVersionF | Distribution.Types.VersionRange.Internal, Distribution.Types.VersionRange, Distribution.Version, Distribution.Simple | 
| orElse |  | 
| 1 (Function) | GHC.Conc.Sync, GHC.Conc | 
| 2 (Function) | Control.Monad.STM, Control.Concurrent.STM | 
| orI# |  | 
| 1 (Function) | GHC.Base, GHC.Exts | 
| 2 (Function) | GHC.PrimopWrappers | 
| 3 (Function) | GHC.Prim | 
| orInteger |  | 
| 1 (Function) | GHC.Integer | 
| 2 (Function) | GHC.Integer.GMP.Internals | 
| OrLaterVersion | Distribution.Types.VersionRange.Internal | 
| orLaterVersion | Distribution.Types.VersionRange.Internal, Distribution.Types.VersionRange, Distribution.Version, Distribution.Simple | 
| OrLaterVersionF | Distribution.Types.VersionRange.Internal, Distribution.Types.VersionRange, Distribution.Version, Distribution.Simple | 
| orNatural | GHC.Natural | 
| orthodoxEaster | Data.Time.Calendar.Easter | 
| orthodoxPaschalMoon | Data.Time.Calendar.Easter | 
| OS |  | 
| 1 (Data Constructor) | Distribution.Types.ConfVar, Distribution.Types.GenericPackageDescription.Lens, Distribution.Types.Lens, Distribution.PackageDescription | 
| 2 (Type/Class) | Distribution.System | 
| 3 (Type/Class) | GHC.Platform | 
| os | System.Info | 
| OSAIX | GHC.Platform | 
| OSDarwin | GHC.Platform | 
| OSDragonFly | GHC.Platform | 
| osElfTarget | GHC.Platform | 
| OSET_PL_2_1 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OSFreeBSD | GHC.Platform | 
| OSHaiku | GHC.Platform | 
| OSHurd | GHC.Platform | 
| OSKFreeBSD | GHC.Platform | 
| OSLinux | GHC.Platform | 
| OSL_1_0 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OSL_1_1 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OSL_2_0 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OSL_2_1 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| OSL_3_0 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| osMachOTarget | GHC.Platform | 
| OSMinGW32 | GHC.Platform | 
| OSNetBSD | GHC.Platform | 
| OSOpenBSD | GHC.Platform | 
| OSQNXNTO | GHC.Platform | 
| OSSolaris2 | GHC.Platform | 
| osSubsectionsViaSymbols | GHC.Platform | 
| OSUnknown | GHC.Platform | 
| OSVar | Distribution.Simple.InstallDirs.Internal, Distribution.Simple.InstallDirs, Distribution.Simple.LocalBuildInfo | 
| OSX | Distribution.System | 
| Other | Control.Applicative.Lift | 
| OtherArch | Distribution.System | 
| OtherClosure | GHC.Exts.Heap.Closures, GHC.Exts.Heap | 
| OtherCompiler | Distribution.Compiler, Distribution.Simple.Compiler, Distribution.Simple | 
| OtherError |  | 
| 1 (Data Constructor) | GHC.IO.Exception | 
| 2 (Data Constructor) | System.Directory.Internal.Prelude | 
| otherExecuteMode | System.Posix.Files.ByteString, System.Posix.Files, System.Posix.ByteString, System.Posix | 
| otherExtensions |  | 
| 1 (Function) | Distribution.Types.BuildInfo.Lens, Distribution.Types.Lens | 
| 2 (Function) | Distribution.Types.BuildInfo, Distribution.PackageDescription | 
| otherLanguages |  | 
| 1 (Function) | Distribution.Types.BuildInfo.Lens, Distribution.Types.Lens | 
| 2 (Function) | Distribution.Types.BuildInfo, Distribution.PackageDescription | 
| OtherLetter | GHC.Unicode, Data.Char | 
| OtherLicense | Distribution.License, Distribution.Make, Distribution.Simple | 
| otherModes | System.Posix.Files.ByteString, System.Posix.Files, System.Posix.ByteString, System.Posix | 
| otherModules |  | 
| 1 (Function) | Distribution.Types.BuildInfo.Lens, Distribution.Types.Lens | 
| 2 (Function) | Distribution.Types.BuildInfo, Distribution.PackageDescription | 
| OtherNumber | GHC.Unicode, Data.Char | 
| OtherOS | Distribution.System | 
| OtherPunctuation | GHC.Unicode, Data.Char | 
| otherReadMode | System.Posix.Files.ByteString, System.Posix.Files, System.Posix.ByteString, System.Posix | 
| OtherRepoType | Distribution.Types.SourceRepo, Distribution.PackageDescription | 
| OtherSymbol | GHC.Unicode, Data.Char | 
| otherwise |  | 
| 1 (Function) | Distribution.Compat.Prelude.Internal | 
| 2 (Function) | GHC.Base, Data.Bool, Prelude | 
| 3 (Function) | System.Directory.Internal.Prelude | 
| otherWriteMode | System.Posix.Files.ByteString, System.Posix.Files, System.Posix.ByteString, System.Posix | 
| outdegree | Data.Graph | 
| outer | Data.Type.Equality | 
| OutputCap | System.Console.Terminfo.Base, System.Console.Terminfo | 
| outputNL | System.IO, GHC.IO.Handle.Types, GHC.IO.Handle | 
| OutputQueue | System.Posix.Terminal.ByteString, System.Posix.Terminal, System.Posix.ByteString, System.Posix | 
| outputSpeed | System.Posix.Terminal.ByteString, System.Posix.Terminal, System.Posix.ByteString, System.Posix | 
| outputStr | System.Console.Haskeline | 
| outputStrLn | System.Console.Haskeline | 
| OutputUnderflow | GHC.IO.Encoding, GHC.IO.Encoding.Types | 
| over | Distribution.Compat.Lens | 
| Overflow | GHC.Exception, Control.Exception, Control.Exception.Base, GHC.Exception.Type | 
| overflowError | GHC.Real | 
| overflowException | GHC.Exception, GHC.Exception.Type | 
| Overlap | Language.Haskell.TH.Syntax, Language.Haskell.TH.Lib, Language.Haskell.TH | 
| Overlappable | Language.Haskell.TH.Syntax, Language.Haskell.TH.Lib, Language.Haskell.TH | 
| Overlapping | Language.Haskell.TH.Syntax, Language.Haskell.TH.Lib, Language.Haskell.TH | 
| OverlappingInstances |  | 
| 1 (Data Constructor) | Language.Haskell.Extension, Distribution.Simple | 
| 2 (Data Constructor) | GHC.LanguageExtensions.Type | 
| 3 (Data Constructor) | GHC.LanguageExtensions | 
| 4 (Data Constructor) | Language.Haskell.TH.LanguageExtensions, Language.Haskell.TH.Syntax, Language.Haskell.TH | 
| Overlaps | Language.Haskell.TH.Syntax, Language.Haskell.TH.Lib, Language.Haskell.TH | 
| OverloadedLabels |  | 
| 1 (Data Constructor) | Language.Haskell.Extension, Distribution.Simple | 
| 2 (Data Constructor) | GHC.LanguageExtensions.Type | 
| 3 (Data Constructor) | GHC.LanguageExtensions | 
| 4 (Data Constructor) | Language.Haskell.TH.LanguageExtensions, Language.Haskell.TH.Syntax, Language.Haskell.TH | 
| OverloadedLists |  | 
| 1 (Data Constructor) | Language.Haskell.Extension, Distribution.Simple | 
| 2 (Data Constructor) | GHC.LanguageExtensions.Type | 
| 3 (Data Constructor) | GHC.LanguageExtensions | 
| 4 (Data Constructor) | Language.Haskell.TH.LanguageExtensions, Language.Haskell.TH.Syntax, Language.Haskell.TH | 
| OverloadedStrings |  | 
| 1 (Data Constructor) | Language.Haskell.Extension, Distribution.Simple | 
| 2 (Data Constructor) | GHC.LanguageExtensions.Type | 
| 3 (Data Constructor) | GHC.LanguageExtensions | 
| 4 (Data Constructor) | Language.Haskell.TH.LanguageExtensions, Language.Haskell.TH.Syntax, Language.Haskell.TH | 
| overNubList | Distribution.Utils.NubList | 
| overNubListR | Distribution.Utils.NubList | 
| owner | GHC.Exts.Heap.Closures, GHC.Exts.Heap | 
| ownerExecuteMode | System.Posix.Files.ByteString, System.Posix.Files, System.Posix.ByteString, System.Posix | 
| ownerModes | System.Posix.Files.ByteString, System.Posix.Files, System.Posix.ByteString, System.Posix | 
| ownerReadMode | System.Posix.Files.ByteString, System.Posix.Files, System.Posix.ByteString, System.Posix | 
| ownerWriteMode | System.Posix.Files.ByteString, System.Posix.Files, System.Posix.ByteString, System.Posix | 
| o_APPEND | System.Posix.Internals | 
| o_BINARY | System.Posix.Internals | 
| o_CREAT | System.Posix.Internals | 
| o_EXCL | System.Posix.Internals | 
| o_NOCTTY | System.Posix.Internals | 
| o_NONBLOCK | System.Posix.Internals | 
| o_RDONLY | System.Posix.Internals | 
| o_RDWR | System.Posix.Internals | 
| o_TRUNC | System.Posix.Internals | 
| O_UDA_1_0 | Distribution.SPDX.LicenseId, Distribution.SPDX | 
| o_WRONLY | System.Posix.Internals |