ghc-9.13: The GHC API
Safe HaskellNone
LanguageGHC2021

GHC.Data.OsPath

Synopsis

OsPath initialisation and transformation

type OsPath = OsString Source #

Type representing filenames/pathnames.

This type doesn't add any guarantees over OsString.

data OsString Source #

Newtype representing short operating system specific strings.

Internally this is either WindowsString or PosixString, depending on the platform. Both use unpinned ShortByteString for efficiency.

The constructor is only exported via System.OsString.Internal.Types, since dealing with the internals isn't generally recommended, but supported in case you need to write platform specific code.

Instances

Instances details
NFData OsString Source # 
Instance details

Defined in System.OsString.Internal.Types

Methods

rnf :: OsString -> () Source #

Monoid OsString Source #

"String-Concatenation" for OsString. This is not the same as (</>).

Instance details

Defined in System.OsString.Internal.Types

Semigroup OsString Source # 
Instance details

Defined in System.OsString.Internal.Types

Generic OsString Source # 
Instance details

Defined in System.OsString.Internal.Types

Associated Types

type Rep OsString 
Instance details

Defined in System.OsString.Internal.Types

type Rep OsString = D1 ('MetaData "OsString" "System.OsString.Internal.Types" "os-string-2.0.4-inplace" 'True) (C1 ('MetaCons "OsString" 'PrefixI 'True) (S1 ('MetaSel ('Just "getOsString") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 PlatformString)))

Methods

from :: OsString -> Rep OsString x #

to :: Rep OsString x -> OsString #

Show OsString Source #

On windows, decodes as UCS-2. On unix prints the raw bytes without decoding.

Instance details

Defined in System.OsString.Internal.Types

Eq OsString Source #

Byte equality of the internal representation.

Instance details

Defined in System.OsString.Internal.Types

Ord OsString Source #

Byte ordering of the internal representation.

Instance details

Defined in System.OsString.Internal.Types

Lift OsString 
Instance details

Defined in System.OsString.Internal.Types

Methods

lift :: Quote m => OsString -> m Exp

liftTyped :: forall (m :: Type -> Type). Quote m => OsString -> Code m OsString

type Rep OsString Source # 
Instance details

Defined in System.OsString.Internal.Types

type Rep OsString = D1 ('MetaData "OsString" "System.OsString.Internal.Types" "os-string-2.0.4-inplace" 'True) (C1 ('MetaCons "OsString" 'PrefixI 'True) (S1 ('MetaSel ('Just "getOsString") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 PlatformString)))

encodeUtf :: MonadThrow m => FilePath -> m OsPath Source #

Partial unicode friendly encoding.

On windows this encodes as UTF16-LE (strictly), which is a pretty good guess. On unix this encodes as UTF8 (strictly), which is a good guess.

Throws an EncodingException if encoding fails. If the input does not contain surrogate chars, you can use unsafeEncodeUtf.

decodeUtf :: MonadThrow m => OsPath -> m FilePath Source #

Partial unicode friendly decoding.

On windows this decodes as UTF16-LE (strictly), which is a pretty good guess. On unix this decodes as UTF8 (strictly), which is a good guess.

Throws a EncodingException if decoding fails.

unsafeDecodeUtf :: HasCallStack => OsPath -> FilePath Source #

Decode an OsPath to FilePath, throwing an error if decoding failed. Prefer decodeUtf and gracious error handling.

unsafeEncodeUtf :: HasCallStack => String -> OsString Source #

Unsafe unicode friendly encoding.

Like encodeUtf, except it crashes when the input contains surrogate chars. For sanitized input, this can be useful.

os :: String -> OsString Source #

Fallibly converts String to OsString. Only intended to be used on literals.

Common utility functions

(</>) :: OsPath -> OsPath -> OsPath Source #

Combine two paths with a path separator. If the second path starts with a path separator or a drive letter, then it returns the second. The intention is that readFile (dir </> file) will access the same file as setCurrentDirectory dir; readFile file.

Posix:   "/directory" </> "file.ext" == "/directory/file.ext"
Windows: "/directory" </> "file.ext" == "/directory\\file.ext"
         "directory" </> "/file.ext" == "/file.ext"
Valid x => (takeDirectory x </> takeFileName x) `equalFilePath` x

Combined:

Posix:   "/" </> "test" == "/test"
Posix:   "home" </> "bob" == "home/bob"
Posix:   "x:" </> "foo" == "x:/foo"
Windows: "C:\\foo" </> "bar" == "C:\\foo\\bar"
Windows: "home" </> "bob" == "home\\bob"

Not combined:

Posix:   "home" </> "/bob" == "/bob"
Windows: "home" </> "C:\\bob" == "C:\\bob"

Not combined (tricky):

On Windows, if a filepath starts with a single slash, it is relative to the root of the current drive. In [1], this is (confusingly) referred to as an absolute path. The current behavior of </> is to never combine these forms.

Windows: "home" </> "/bob" == "/bob"
Windows: "home" </> "\\bob" == "\\bob"
Windows: "C:\\home" </> "\\bob" == "\\bob"

On Windows, from [1]: "If a file name begins with only a disk designator but not the backslash after the colon, it is interpreted as a relative path to the current directory on the drive with the specified letter." The current behavior of </> is to never combine these forms.

Windows: "D:\\foo" </> "C:bar" == "C:bar"
Windows: "C:\\foo" </> "C:bar" == "C:bar"

(<.>) :: OsPath -> OsString -> OsPath Source #

Add an extension, even if there is already one there, equivalent to addExtension.

"/directory/path" <.> "ext" == "/directory/path.ext"
"/directory/path" <.> ".ext" == "/directory/path.ext"