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Diffstat (limited to 'pkgs/lib/strings.nix')
| -rw-r--r-- | pkgs/lib/strings.nix | 190 |
1 files changed, 0 insertions, 190 deletions
diff --git a/pkgs/lib/strings.nix b/pkgs/lib/strings.nix deleted file mode 100644 index 024a9ac7d7a2..000000000000 --- a/pkgs/lib/strings.nix +++ /dev/null @@ -1,190 +0,0 @@ -/* String manipulation functions. */ - -let lib = import ./default.nix; - -inherit (builtins) add sub lessThan length; - -in - -rec { - inherit (builtins) stringLength substring head tail; - - - # Concatenate a list of strings. - concatStrings = lib.fold (x: y: x + y) ""; - - - # Map a function over a list and concatenate the resulting strings. - concatMapStrings = f: list: concatStrings (map f list); - concatImapStrings = f: list: concatStrings (lib.imap f list); - - - # Place an element between each element of a list, e.g., - # `intersperse "," ["a" "b" "c"]' returns ["a" "," "b" "," "c"]. - intersperse = separator: list: - if list == [] || length list == 1 - then list - else [(head list) separator] - ++ (intersperse separator (tail list)); - - - # Concatenate a list of strings with a separator between each element, e.g. - # concatStringsSep " " ["foo" "bar" "xyzzy"] == "foo bar xyzzy" - concatStringsSep = separator: list: - concatStrings (intersperse separator list); - - - # Construct a Unix-style search path consisting of each `subDir" - # directory of the given list of packages. For example, - # `makeSearchPath "bin" ["x" "y" "z"]' returns "x/bin:y/bin:z/bin". - makeSearchPath = subDir: packages: - concatStringsSep ":" (map (path: path + "/" + subDir) packages); - - - # Construct a library search path (such as RPATH) containing the - # libraries for a set of packages, e.g. "${pkg1}/lib:${pkg2}/lib:...". - makeLibraryPath = makeSearchPath "lib"; - - - # Idem for Perl search paths. - makePerlPath = makeSearchPath "lib/perl5/site_perl"; - - - # Dependening on the boolean `cond', return either the given string - # or the empty string. - optionalString = cond: string: if cond then string else ""; - - - # Determine whether a filename ends in the given suffix. - hasSuffix = ext: fileName: - let lenFileName = stringLength fileName; - lenExt = stringLength ext; - in !(lessThan lenFileName lenExt) && - substring (sub lenFileName lenExt) lenFileName fileName == ext; - - - # Convert a string to a list of characters (i.e. singleton strings). - # For instance, "abc" becomes ["a" "b" "c"]. This allows you to, - # e.g., map a function over each character. However, note that this - # will likely be horribly inefficient; Nix is not a general purpose - # programming language. Complex string manipulations should, if - # appropriate, be done in a derivation. - stringToCharacters = s: let l = stringLength s; in - if l == 0 - then [] - else map (p: substring p 1 s) (lib.range 0 (sub l 1)); - - - # Manipulate a string charcater by character and replace them by strings - # before concatenating the results. - stringAsChars = f: s: - concatStrings ( - map f (stringToCharacters s) - ); - - - # same as vim escape function. - # Each character contained in list is prefixed by "\" - escape = list : string : - stringAsChars (c: if lib.elem c list then "\\${c}" else c) string; - - - # still ugly slow. But more correct now - # [] for zsh - escapeShellArg = lib.escape (stringToCharacters "\\ ';$`()|<>\t*[]"); - - - # replace characters by their substitutes. This function is equivalent to - # the `tr' command except that one character can be replace by multiple - # ones. e.g., - # replaceChars ["<" ">"] ["<" ">"] "<foo>" returns "<foo>". - replaceChars = del: new: s: - let - subst = c: - (lib.fold - (sub: res: if sub.fst == c then sub else res) - {fst = c; snd = c;} (lib.zipLists del new) - ).snd; - in - stringAsChars subst s; - - - # Case conversion utilities - lowerChars = stringToCharacters "abcdefghijklmnopqrstuvwxyz"; - upperChars = stringToCharacters "ABCDEFGHIJKLMNOPQRSTUVWXYZ"; - toLower = replaceChars upperChars lowerChars; - toUpper = replaceChars lowerChars upperChars; - - - # Compares strings not requiring context equality - # Obviously, a workaround but works on all Nix versions - eqStrings = a: b: (a+(substring 0 0 b)) == ((substring 0 0 a)+b); - - - # Cut a string with a separator and produces a list of strings which were - # separated by this separator. e.g., - # `splitString "." "foo.bar.baz"' returns ["foo" "bar" "baz"]. - splitString = sep: s: - let - sepLen = stringLength sep; - sLen = stringLength s; - lastSearch = sub sLen sepLen; - startWithSep = startAt: - substring startAt sepLen s == sep; - - recurse = index: startAt: - let cutUntil = i: [(substring startAt (sub i startAt) s)]; in - if lessThan index lastSearch then - if startWithSep index then - let restartAt = add index sepLen; in - cutUntil index ++ recurse restartAt restartAt - else - recurse (add index 1) startAt - else - cutUntil sLen; - in - recurse 0 0; - - - # return the suffix of the second argument if the first argument match its - # prefix. e.g., - # `removePrefix "foo." "foo.bar.baz"' returns "bar.baz". - removePrefix = pre: s: - let - preLen = stringLength pre; - sLen = stringLength s; - in - if pre == substring 0 preLen s then - substring preLen (sub sLen preLen) s - else - s; - - # Return true iff string v1 denotes a version older than v2. - versionOlder = v1: v2: builtins.compareVersions v2 v1 == 1; - - - # Return true iff string v1 denotes a version equal to or newer than v2. - versionAtLeast = v1: v2: !versionOlder v1 v2; - - - # Get the version of the specified derivation, as specified in its - # ‘name’ attribute. - getVersion = drv: (builtins.parseDrvName drv.name).version; - - - # Extract name with version from URL. Ask for separator which is - # supposed to start extension - nameFromURL = url: sep: let - components = splitString "/" url; - filename = lib.last components; - name = builtins.head (splitString sep filename); - in - assert ! eqStrings name filename; - name; - - - # Create an --{enable,disable}-<feat> string that can be passed to - # standard GNU Autoconf scripts. - enableFeature = enable: feat: "--${if enable then "enable" else "disable"}-${feat}"; - -} |