/usr/lib/hugs/packages/base/System/Directory/Internals.hs is in libhugs-base-bundled 98.200609.21-5.4.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 | {-# OPTIONS_GHC -fno-implicit-prelude #-}
-----------------------------------------------------------------------------
-- |
-- Module : System.Directory.Internals
-- Copyright : (c) The University of Glasgow 2005
-- License : BSD-style (see the file libraries/base/LICENSE)
--
-- Maintainer : libraries@haskell.org
-- Stability : hidden
-- Portability : portable
--
-- System-independent pathname manipulations.
--
-----------------------------------------------------------------------------
-- #hide
module System.Directory.Internals (
joinFileName,
joinFileExt,
parseSearchPath,
pathParents,
exeExtension,
) where
import Data.List
-- | The 'joinFileName' function is the opposite of 'splitFileName'.
-- It joins directory and file names to form a complete file path.
--
-- The general rule is:
--
-- > dir `joinFileName` basename == path
-- > where
-- > (dir,basename) = splitFileName path
--
-- There might be an exceptions to the rule but in any case the
-- reconstructed path will refer to the same object (file or directory).
-- An example exception is that on Windows some slashes might be converted
-- to backslashes.
joinFileName :: String -> String -> FilePath
joinFileName "" fname = fname
joinFileName "." fname = fname
joinFileName dir "" = dir
joinFileName dir fname
| isPathSeparator (last dir) = dir++fname
| otherwise = dir++pathSeparator:fname
-- | The 'joinFileExt' function is the opposite of 'splitFileExt'.
-- It joins a file name and an extension to form a complete file path.
--
-- The general rule is:
--
-- > filename `joinFileExt` ext == path
-- > where
-- > (filename,ext) = splitFileExt path
joinFileExt :: String -> String -> FilePath
joinFileExt path "" = path
joinFileExt path ext = path ++ '.':ext
-- | Gets this path and all its parents.
-- The function is useful in case if you want to create
-- some file but you aren\'t sure whether all directories
-- in the path exist or if you want to search upward for some file.
--
-- Some examples:
--
-- \[Posix\]
--
-- > pathParents "/" == ["/"]
-- > pathParents "/dir1" == ["/", "/dir1"]
-- > pathParents "/dir1/dir2" == ["/", "/dir1", "/dir1/dir2"]
-- > pathParents "dir1" == [".", "dir1"]
-- > pathParents "dir1/dir2" == [".", "dir1", "dir1/dir2"]
--
-- \[Windows\]
--
-- > pathParents "c:" == ["c:."]
-- > pathParents "c:\\" == ["c:\\"]
-- > pathParents "c:\\dir1" == ["c:\\", "c:\\dir1"]
-- > pathParents "c:\\dir1\\dir2" == ["c:\\", "c:\\dir1", "c:\\dir1\\dir2"]
-- > pathParents "c:dir1" == ["c:.","c:dir1"]
-- > pathParents "dir1\\dir2" == [".", "dir1", "dir1\\dir2"]
--
-- Note that if the file is relative then the current directory (\".\")
-- will be explicitly listed.
pathParents :: FilePath -> [FilePath]
pathParents p =
root'' : map ((++) root') (dropEmptyPath $ inits path')
where
(root,path) = ("",p)
(root',root'',path') = case path of
(c:path) | isPathSeparator c -> (root++[pathSeparator],root++[pathSeparator],path)
_ -> (root ,root++"." ,path)
dropEmptyPath ("":paths) = paths
dropEmptyPath paths = paths
inits :: String -> [String]
inits [] = [""]
inits cs =
case pre of
"." -> inits suf
".." -> map (joinFileName pre) (dropEmptyPath $ inits suf)
_ -> "" : map (joinFileName pre) (inits suf)
where
(pre,suf) = case break isPathSeparator cs of
(pre,"") -> (pre, "")
(pre,_:suf) -> (pre,suf)
--------------------------------------------------------------
-- * Search path
--------------------------------------------------------------
-- | The function splits the given string to substrings
-- using the 'searchPathSeparator'.
parseSearchPath :: String -> [FilePath]
parseSearchPath path = split path
where
split :: String -> [String]
split s =
case rest' of
[] -> [chunk]
_:rest -> chunk : split rest
where
chunk =
case chunk' of
_ -> chunk'
(chunk', rest') = break (==searchPathSeparator) s
--------------------------------------------------------------
-- * Separators
--------------------------------------------------------------
-- | Checks whether the character is a valid path separator for the host
-- platform. The valid character is a 'pathSeparator' but since the Windows
-- operating system also accepts a slash (\"\/\") since DOS 2, the function
-- checks for it on this platform, too.
isPathSeparator :: Char -> Bool
isPathSeparator ch = ch == pathSeparator || ch == '/'
-- | Provides a platform-specific character used to separate directory levels in
-- a path string that reflects a hierarchical file system organization. The
-- separator is a slash (@\"\/\"@) on Unix and Macintosh, and a backslash
-- (@\"\\\"@) on the Windows operating system.
pathSeparator :: Char
pathSeparator = '/'
-- ToDo: This should be determined via autoconf (PATH_SEPARATOR)
-- | A platform-specific character used to separate search path strings in
-- environment variables. The separator is a colon (@\":\"@) on Unix and
-- Macintosh, and a semicolon (@\";\"@) on the Windows operating system.
searchPathSeparator :: Char
searchPathSeparator = ':'
-- ToDo: This should be determined via autoconf (AC_EXEEXT)
-- | Extension for executable files
-- (typically @\"\"@ on Unix and @\"exe\"@ on Windows or OS\/2)
exeExtension :: String
exeExtension = ""
|