Path::Class::Dir - phpMan

NAME
    Path::Class::Dir - Objects representing directories

VERSION
    version 0.37

SYNOPSIS
      use Path::Class;  # Exports dir() by default

      my $dir = dir('foo', 'bar');       # Path::Class::Dir object
      my $dir = Path::Class::Dir->new('foo', 'bar');  # Same thing

      # Stringifies to 'foo/bar' on Unix, 'foo\bar' on Windows, etc.
      print "dir: $dir\n";

      if ($dir->is_absolute) { ... }
      if ($dir->is_relative) { ... }

      my $v = $dir->volume; # Could be 'C:' on Windows, empty string
                            # on Unix, 'Macintosh HD:' on Mac OS

      $dir->cleanup; # Perform logical cleanup of pathname
      $dir->resolve; # Perform physical cleanup of pathname

      my $file = $dir->file('file.txt'); # A file in this directory
      my $subdir = $dir->subdir('george'); # A subdirectory
      my $parent = $dir->parent; # The parent directory, 'foo'

      my $abs = $dir->absolute; # Transform to absolute path
      my $rel = $abs->relative; # Transform to relative path
      my $rel = $abs->relative('/foo'); # Relative to /foo

      print $dir->as_foreign('Mac');   # :foo:bar:
      print $dir->as_foreign('Win32'); #  foo\bar

      # Iterate with IO::Dir methods:
      my $handle = $dir->open;
      while (my $file = $handle->read) {
        $file = $dir->file($file);  # Turn into Path::Class::File object
        ...
      }

      # Iterate with Path::Class methods:
      while (my $file = $dir->next) {
        # $file is a Path::Class::File or Path::Class::Dir object
        ...
      }

DESCRIPTION
    The "Path::Class::Dir" class contains functionality for manipulating
    directory names in a cross-platform way.

METHODS
    $dir = Path::Class::Dir->new( <dir1>, <dir2>, ... )
    $dir = dir( <dir1>, <dir2>, ... )
        Creates a new "Path::Class::Dir" object and returns it. The
        arguments specify names of directories which will be joined to
        create a single directory object. A volume may also be specified as
        the first argument, or as part of the first argument. You can use
        platform-neutral syntax:

          my $dir = dir( 'foo', 'bar', 'baz' );

        or platform-native syntax:

          my $dir = dir( 'foo/bar/baz' );

        or a mixture of the two:

          my $dir = dir( 'foo/bar', 'baz' );

        All three of the above examples create relative paths. To create an
        absolute path, either use the platform native syntax for doing so:

          my $dir = dir( '/var/tmp' );

        or use an empty string as the first argument:

          my $dir = dir( '', 'var', 'tmp' );

        If the second form seems awkward, that's somewhat intentional -
        paths like "/var/tmp" or "\Windows" aren't cross-platform concepts
        in the first place (many non-Unix platforms don't have a notion of a
        "root directory"), so they probably shouldn't appear in your code if
        you're trying to be cross-platform. The first form is perfectly
        natural, because paths like this may come from config files, user
        input, or whatever.

        As a special case, since it doesn't otherwise mean anything useful
        and it's convenient to define this way, "Path::Class::Dir->new()"
        (or "dir()") refers to the current directory ("File::Spec->curdir").
        To get the current directory as an absolute path, do
        "dir()->absolute".

        Finally, as another special case "dir(undef)" will return undef,
        since that's usually an accident on the part of the caller, and
        returning the root directory would be a nasty surprise just asking
        for trouble a few lines later.

    $dir->stringify
        This method is called internally when a "Path::Class::Dir" object is
        used in a string context, so the following are equivalent:

          $string = $dir->stringify;
          $string = "$dir";

    $dir->volume
        Returns the volume (e.g. "C:" on Windows, "Macintosh HD:" on Mac OS,
        etc.) of the directory object, if any. Otherwise, returns the empty
        string.

    $dir->basename
        Returns the last directory name of the path as a string.

    $dir->is_dir
        Returns a boolean value indicating whether this object represents a
        directory. Not surprisingly, Path::Class::File objects always return
        false, and "Path::Class::Dir" objects always return true.

    $dir->is_absolute
        Returns true or false depending on whether the directory refers to
        an absolute path specifier (like "/usr/local" or "\Windows").

    $dir->is_relative
        Returns true or false depending on whether the directory refers to a
        relative path specifier (like "lib/foo" or "./dir").

    $dir->cleanup
        Performs a logical cleanup of the file path. For instance:

          my $dir = dir('/foo//baz/./foo')->cleanup;
          # $dir now represents '/foo/baz/foo';

    $dir->resolve
        Performs a physical cleanup of the file path. For instance:

          my $dir = dir('/foo//baz/../foo')->resolve;
          # $dir now represents '/foo/foo', assuming no symlinks

        This actually consults the filesystem to verify the validity of the
        path.

    $file = $dir->file( <dir1>, <dir2>, ..., <file> )
        Returns a Path::Class::File object representing an entry in $dir or
        one of its subdirectories. Internally, this just calls
        "Path::Class::File->new( @_ )".

    $subdir = $dir->subdir( <dir1>, <dir2>, ... )
        Returns a new "Path::Class::Dir" object representing a subdirectory
        of $dir.

    $parent = $dir->parent
        Returns the parent directory of $dir. Note that this is the
        *logical* parent, not necessarily the physical parent. It really
        means we just chop off entries from the end of the directory list
        until we cain't chop no more. If the directory is relative, we start
        using the relative forms of parent directories.

        The following code demonstrates the behavior on absolute and
        relative directories:

          $dir = dir('/foo/bar');
          for (1..6) {
            print "Absolute: $dir\n";
            $dir = $dir->parent;
          }

          $dir = dir('foo/bar');
          for (1..6) {
            print "Relative: $dir\n";
            $dir = $dir->parent;
          }

          ########### Output on Unix ################
          Absolute: /foo/bar
          Absolute: /foo
          Absolute: /
          Absolute: /
          Absolute: /
          Absolute: /
          Relative: foo/bar
          Relative: foo
          Relative: .
          Relative: ..
          Relative: ../..
          Relative: ../../..

    @list = $dir->children
        Returns a list of Path::Class::File and/or "Path::Class::Dir"
        objects listed in this directory, or in scalar context the number of
        such objects. Obviously, it is necessary for $dir to exist and be
        readable in order to find its children.

        Note that the children are returned as subdirectories of $dir, i.e.
        the children of foo will be foo/bar and foo/baz, not bar and baz.

        Ordinarily "children()" will not include the *self* and *parent*
        entries "." and ".." (or their equivalents on non-Unix systems),
        because that's like I'm-my-own-grandpa business. If you do want all
        directory entries including these special ones, pass a true value
        for the "all" parameter:

          @c = $dir->children(); # Just the children
          @c = $dir->children(all => 1); # All entries

        In addition, there's a "no_hidden" parameter that will exclude all
        normally "hidden" entries - on Unix this means excluding all entries
        that begin with a dot ("."):

          @c = $dir->children(no_hidden => 1); # Just normally-visible entries

    $abs = $dir->absolute
        Returns a "Path::Class::Dir" object representing $dir as an absolute
        path. An optional argument, given as either a string or a
        "Path::Class::Dir" object, specifies the directory to use as the
        base of relativity - otherwise the current working directory will be
        used.

    $rel = $dir->relative
        Returns a "Path::Class::Dir" object representing $dir as a relative
        path. An optional argument, given as either a string or a
        "Path::Class::Dir" object, specifies the directory to use as the
        base of relativity - otherwise the current working directory will be
        used.

    $boolean = $dir->subsumes($other)
        Returns true if this directory spec subsumes the other spec, and
        false otherwise. Think of "subsumes" as "contains", but we only look
        at the *specs*, not whether $dir actually contains $other on the
        filesystem.

        The $other argument may be a "Path::Class::Dir" object, a
        Path::Class::File object, or a string. In the latter case, we assume
        it's a directory.

          # Examples:
          dir('foo/bar' )->subsumes(dir('foo/bar/baz'))  # True
          dir('/foo/bar')->subsumes(dir('/foo/bar/baz')) # True
          dir('foo/..')->subsumes(dir('foo/../bar))      # True
          dir('foo/bar' )->subsumes(dir('bar/baz'))      # False
          dir('/foo/bar')->subsumes(dir('foo/bar'))      # False
          dir('foo/..')->subsumes(dir('bar'))            # False! Use C<contains> to resolve ".."

    $boolean = $dir->contains($other)
        Returns true if this directory actually contains $other on the
        filesystem. $other doesn't have to be a direct child of $dir, it
        just has to be subsumed after both paths have been resolved.

    $foreign = $dir->as_foreign($type)
        Returns a "Path::Class::Dir" object representing $dir as it would be
        specified on a system of type $type. Known types include "Unix",
        "Win32", "Mac", "VMS", and "OS2", i.e. anything for which there is a
        subclass of "File::Spec".

        Any generated objects (subdirectories, files, parents, etc.) will
        also retain this type.

    $foreign = Path::Class::Dir->new_foreign($type, @args)
        Returns a "Path::Class::Dir" object representing $dir as it would be
        specified on a system of type $type. Known types include "Unix",
        "Win32", "Mac", "VMS", and "OS2", i.e. anything for which there is a
        subclass of "File::Spec".

        The arguments in @args are the same as they would be specified in
        "new()".

    @list = $dir->dir_list([OFFSET, [LENGTH]])
        Returns the list of strings internally representing this directory
        structure. Each successive member of the list is understood to be an
        entry in its predecessor's directory list. By contract,
        "Path::Class->new( $dir->dir_list )" should be equivalent to $dir.

        The semantics of this method are similar to Perl's "splice" or
        "substr" functions; they return "LENGTH" elements starting at
        "OFFSET". If "LENGTH" is omitted, returns all the elements starting
        at "OFFSET" up to the end of the list. If "LENGTH" is negative,
        returns the elements from "OFFSET" onward except for "-LENGTH"
        elements at the end. If "OFFSET" is negative, it counts backward
        "OFFSET" elements from the end of the list. If "OFFSET" and "LENGTH"
        are both omitted, the entire list is returned.

        In a scalar context, "dir_list()" with no arguments returns the
        number of entries in the directory list; "dir_list(OFFSET)" returns
        the single element at that offset; "dir_list(OFFSET, LENGTH)"
        returns the final element that would have been returned in a list
        context.

    $dir->components
        Identical to "dir_list()". It exists because there's an analogous
        method "dir_list()" in the "Path::Class::File" class that also
        returns the basename string, so this method lets someone call
        "components()" without caring whether the object is a file or a
        directory.

    $fh = $dir->open()
        Passes $dir to "IO::Dir->open" and returns the result as an IO::Dir
        object. If the opening fails, "undef" is returned and $! is set.

    $dir->mkpath($verbose, $mode)
        Passes all arguments, including $dir, to "File::Path::mkpath()" and
        returns the result (a list of all directories created).

    $dir->rmtree($verbose, $cautious)
        Passes all arguments, including $dir, to "File::Path::rmtree()" and
        returns the result (the number of files successfully deleted).

    $dir->remove()
        Removes the directory, which must be empty. Returns a boolean value
        indicating whether or not the directory was successfully removed.
        This method is mainly provided for consistency with
        "Path::Class::File"'s "remove()" method.

    $dir->tempfile(...)
        An interface to File::Temp's "tempfile()" function. Just like that
        function, if you call this in a scalar context, the return value is
        the filehandle and the file is "unlink"ed as soon as possible (which
        is immediately on Unix-like platforms). If called in a list context,
        the return values are the filehandle and the filename.

        The given directory is passed as the "DIR" parameter.

        Here's an example of pretty good usage which doesn't allow race
        conditions, won't leave yucky tempfiles around on your filesystem,
        etc.:

          my $fh = $dir->tempfile;
          print $fh "Here's some data...\n";
          seek($fh, 0, 0);
          while (<$fh>) { do something... }

        Or in combination with a "fork":

          my $fh = $dir->tempfile;
          print $fh "Here's some more data...\n";
          seek($fh, 0, 0);
          if ($pid=fork()) {
            wait;
          } else {
            something($_) while <$fh>;
          }

    $dir_or_file = $dir->next()
        A convenient way to iterate through directory contents. The first
        time "next()" is called, it will "open()" the directory and read the
        first item from it, returning the result as a "Path::Class::Dir" or
        Path::Class::File object (depending, of course, on its actual type).
        Each subsequent call to "next()" will simply iterate over the
        directory's contents, until there are no more items in the
        directory, and then the undefined value is returned. For example, to
        iterate over all the regular files in a directory:

          while (my $file = $dir->next) {
            next unless -f $file;
            my $fh = $file->open('r') or die "Can't read $file: $!";
            ...
          }

        If an error occurs when opening the directory (for instance, it
        doesn't exist or isn't readable), "next()" will throw an exception
        with the value of $!.

    $dir->traverse( sub { ... }, @args )
        Calls the given callback for the root, passing it a continuation
        function which, when called, will call this recursively on each of
        its children. The callback function should be of the form:

          sub {
            my ($child, $cont, @args) = @_;
            # ...
          }

        For instance, to calculate the number of files in a directory, you
        can do this:

          my $nfiles = $dir->traverse(sub {
            my ($child, $cont) = @_;
            return sum($cont->(), ($child->is_dir ? 0 : 1));
          });

        or to calculate the maximum depth of a directory:

          my $depth = $dir->traverse(sub {
            my ($child, $cont, $depth) = @_;
            return max($cont->($depth + 1), $depth);
          }, 0);

        You can also choose not to call the callback in certain situations:

          $dir->traverse(sub {
            my ($child, $cont) = @_;
            return if -l $child; # don't follow symlinks
            # do something with $child
            return $cont->();
          });

    $dir->traverse_if( sub { ... }, sub { ... }, @args )
        traverse with additional "should I visit this child" callback.
        Particularly useful in case examined tree contains inaccessible
        directories.

        Canonical example:

          $dir->traverse_if(
            sub {
               my ($child, $cont) = @_;
               # do something with $child
               return $cont->();
            },
            sub {
               my ($child) = @_;
               # Process only readable items
               return -r $child;
            });

        Second callback gets single parameter: child. Only children for
        which it returns true will be processed by the first callback.

        Remaining parameters are interpreted as in traverse, in particular
        "traverse_if(callback, sub { 1 }, @args" is equivalent to
        "traverse(callback, @args)".

    $dir->recurse( callback => sub {...} )
        Iterates through this directory and all of its children, and all of
        its children's children, etc., calling the "callback" subroutine for
        each entry. This is a lot like what the File::Find module does, and
        of course "File::Find" will work fine on Path::Class objects, but
        the advantage of the "recurse()" method is that it will also feed
        your callback routine "Path::Class" objects rather than just
        pathname strings.

        The "recurse()" method requires a "callback" parameter specifying
        the subroutine to invoke for each entry. It will be passed the
        "Path::Class" object as its first argument.

        "recurse()" also accepts two boolean parameters, "depthfirst" and
        "preorder" that control the order of recursion. The default is a
        preorder, breadth-first search, i.e. "depthfirst => 0, preorder =>
        1". At the time of this writing, all combinations of these two
        parameters are supported *except* "depthfirst => 0, preorder => 0".

        "callback" is normally not required to return any value. If it
        returns special constant "Path::Class::Entity::PRUNE()" (more easily
        available as "$item->PRUNE"), no children of analyzed item will be
        analyzed (mostly as if you set "$File::Find::prune=1"). Of course
        pruning is available only in "preorder", in postorder return value
        has no effect.

    $st = $file->stat()
        Invokes "File::stat::stat()" on this directory and returns a
        "File::stat" object representing the result.

    $st = $file->lstat()
        Same as "stat()", but if $file is a symbolic link, "lstat()" stats
        the link instead of the directory the link points to.

    $class = $file->file_class()
        Returns the class which should be used to create file objects.

        Generally overridden whenever this class is subclassed.

AUTHOR
    Ken Williams, kwilliams AT cpan.org

SEE ALSO
    Path::Class, Path::Class::File, File::Spec