class IO::Path is Cool does IO { }

IO::Path is the workhorse of IO operations.

Conceptually, an IO::Path object consists of a volume, a directory, and a basename. It supports both purely textual operations, and operations that access the filesystem, e.g. to resolve a path, or to read all content of a file.

At creation, each IO::Path object is given information about the current working directory the path might be relative to using the $.CWD attribute (defaults to $*CWD), as well as what operating system semantics should be used for path manipulation using the special IO::Spec type given in the $.SPEC attribute.

The $.SPEC defaults to the value of $*SPEC, which uses the object suitable for the operating system the code is currently running on. This is the default most code will be comfortable with.

In certain situations, e.g. testing, you may wish to force $*SPEC to use one of the specific SPEC modules: IO::Spec::Unix, IO::Spec::Win32, IO::Spec::Cygwin, and IO::Spec::QNX, or to create IO::Path objects via shortcut subclasses IO::Path::Unix, IO::Path::Win32, IO::Path::Cygwin, and IO::Path::QNX that pre-set the $.SPEC attribute for you.

The rest of this document silently assumes Unix semantics in its examples, unless stated otherwise.

Methods

method new

Defined as:

multi method new(Str:D $path, IO::Spec :$SPEC = $*SPEC, Str() :$CWD = $*CWD)
multi method new(
    :$basename!, :$dirname = '.', :$volume = ''
    IO::Spec :$SPEC = $*SPEC, Str() :$CWD = $*CWD
)

Creates a new IO::Path object from a path string (which is being parsed for volume, directory name and basename), or from volume, directory name and basename passed as named arguments.

The path's operation will be performed using :$SPEC semantics (defaults to current $*SPEC) and will use :$CWD as the directory the path is relative to (defaults to $*CWD).

attribute CWD

IO::Path.new("foo", :CWD</home/camelia>)
    .CWD.say; # OUTPUT: «/home/camelia␤»

Read-only. Contains implicit or explicit value of :$CWD argument to .new.

attribute SPEC

IO::Path.new("foo", :SPEC(IO::Spec::Unix.new))\
    .SPEC.^name.say; # OUTPUT: «IO::Spec::Unix␤»

Read-only. Contains implicit or explicit value of :$SPEC argument to .new.

attribute path

IO::Path.new("foo").path.say; # OUTPUT: «foo␤»

Read-only. Returns the string the object was constructed from or the value of $SPEC.join($volume, $dirname, $basename) if multi-part version of .new was used. NOTE: this does not include the $.CWD; see IO::Path.absolute and IO::Path.relative for stringification options that include $.CWD.

NOTE: Implementations may cache operations done with this attribute, so modifying its value (via cloning or Proxy) is NOT recommended and may result in broken IO::Path objects. Create a new IO::Path object instead.

method ACCEPTS

Defined as:

multi method ACCEPTS(IO::Path:D: Cool:D $other --> Bool:D)

Coerces the argument to IO::Path, if necessary. Returns True if .absolute method on both paths returns the same string. NOTE: it's possible for two paths that superficially point to the same resource to NOT smartmatch as True, if they were constructed differently and were never fully resolved:

say "foo/../bar".IO ~~ "bar".IO # False

The reason is the two paths above may point to different resources when fully resolved (e.g. if foo is a symlink). Resolve the paths before smartmatching to check they point to same resource:

say "foo/../bar".IO.resolve(:completely) ~~ "bar".IO.resolve(:completely) # True

method basename

Defined as:

method basename(IO::Path:D:)

Returns the basename part of the path object, which is the name of the filesystem object itself that is referenced by the path.

"docs/README.pod".IO.basename.say; # OUTPUT: «README.pod␤» 
"/tmp/".IO.basename.say;           # OUTPUT: «tmp␤»

Note that in IO::Spec::Win32 semantics, the basename of a Windows share is \, not the name of the share itself:

IO::Path::Win32.new('//server/share').basename.say; # OUTPUT: «\␤»

method add

Defined as:

method add(IO::Path:D: Str() $what --> IO::Path:D)

Concatenates a path fragment to the invocant and returns the resultant IO::Path. If adding ../ to paths that end with a file, you may need to call resolve for the resultant path to be accessible by other IO::Path methods like dir or open. See also sibling and parent.

"foo/bar".IO.mkdir;
"foo/bar".IO.add("meow")    .resolve.relative.say; # OUTPUT: «foo/bar/meow␤» 
"foo/bar".IO.add("/meow")   .resolve.relative.say; # OUTPUT: «foo/bar/meow␤» 
"foo/bar".IO.add("meow.txt").resolve.relative.say; # OUTPUT: «foo/bar/meow.txt␤» 
"foo/bar".IO.add("../meow") .resolve.relative.say; # OUTPUT: «foo/meow␤» 
"foo/bar".IO.add("../../")  .resolve.relative.say; # OUTPUT: «.␤»

method child

Defined as:

method child(IO::Path:D: Str() $childname --> IO::Path:D)

Alias for .add. NOTE: This method has been deprecated as of the 6.d version, and will be removed in the future. For any new code, please use .add

method cleanup

Defined as:

method cleanup(IO::Path:D: --> IO::Path:D)

Returns a new path that is a canonical representation of the invocant path, cleaning up any extraneous path parts:

"foo/./././..////bar".IO.cleanup.say;      # OUTPUT: «"foo/../bar".IO␤» 
IO::Path::Win32.new("foo/./././..////bar")
    .cleanup.say; "foo\..\bar".IO;         # OUTPUT: «"foo\..\bar".IO␤»

Note that no filesystem access is made. See also resolve.

method comb

Defined as:

method comb(IO::Path:D: |args --> Seq:D)

Opens the file and processes its contents the same way Str.comb does, taking the same arguments. Implementations may slurp the file in its entirety when this method is called.

method split

Defined as:

method split(IO::Path:D: |args --> Seq:D)

Opens the file and processes its contents the same way Str.split does, taking the same arguments. Implementations may slurp the file in its entirety when this method is called.

method extension

Defined as:

multi method extension(IO::Path:D:                                         --> Str:D)
multi method extension(IO::Path:D:               Int :$parts               --> Str:D)
multi method extension(IO::Path:D:             Range :$parts               --> Str:D)
multi method extension(IO::Path:D: Str $subst,   Int :$parts, Str :$joiner --> IO::Path:D)
multi method extension(IO::Path:D: Str $subst, Range :$parts, Str :$joiner --> IO::Path:D)

Returns the extension consisting of $parts parts (defaults to 1), where a "part" is defined as a dot followed by possibly-empty string up to the end of the string, or previous part. That is "foo.tar.gz" has an extension of two parts: first part is "gz" and second part is "tar" and calling "foo.tar.gz".IO.extension: :2parts gives "tar.gz". If an extension with the specified number of $parts is not found, returns an empty string.

$parts can be a Range, specifying the minimum number of parts and maximum number of parts the extension should have. The routine will attempt to much the most parts it can. If $parts range's endpoints that are smaller than 0 they'll be treated as 0; implementations may treat endpoints larger than 2⁶³-1 as 2⁶³-1. Ranges with NaN or Str endpoints will cause an exception to be thrown.

If $subst is provided, the extension will be instead replaced with $subst and a new IO::Path object will be returned. It will be joined to the file's name with $joiner, which defaults to an empty string when $subst is an empty string and to "." when $subst is not empty. Note: if as the result of replacement the basename of the path ends up being empty, it will be assumed to be . (a single dot).

# Getting an extension: 
say "foo.tar.gz".IO.extension;               # OUTPUT: «gz␤» 
say "foo.tar.gz".IO.extension: :2parts;      # OUTPUT: «tar.gz␤» 
say "foo.tar.gz".IO.extension: :parts(^5);   # OUTPUT: «tar.gz␤» 
say "foo.tar.gz".IO.extension: :parts(0..1); # OUTPUT: «gz␤» 
 
# Replacing an extension 
say "foo.tar.gz".IO.extension: '';                # OUTPUT: «"foo.tar".IO␤» 
say "foo.tar.gz".IO.extension: 'ZIP';             # OUTPUT: «"foo.tar.ZIP".IO␤» 
say "foo.tar.gz".IO.extension: 'ZIP', :0parts;    # OUTPUT: «"foo.tar.gz.ZIP".IO␤» 
say "foo.tar.gz".IO.extension: 'ZIP', :2parts;    # OUTPUT: «"foo.ZIP".IO␤» 
say "foo.tar.gz".IO.extension: 'ZIP', :parts(^5); # OUTPUT: «"foo.ZIP".IO␤» 
 
# Replacing an extension using non-standard joiner: 
say "foo.tar.gz".IO.extension: '',    :joiner<_>;  # OUTPUT: «"foo.tar_".IO␤» 
say "foo.tar.gz".IO.extension: 'ZIP', :joiner<_>;  # OUTPUT: «"foo.tar_ZIP".IO␤» 
say "foo.tar.gz".IO.extension: 'ZIP', :joiner<_>,
                                       :2parts;     # OUTPUT: «"foo_ZIP".IO␤» 
say "foo.tar.gz".IO.extension: 'ZIP', :joiner<_>,
                                       :parts(^5);  # OUTPUT: «"foo_ZIP".IO␤» 
 
# EDGE CASES: 
 
# There is no 5-part extension, so returned value is an empty string 
say "foo.tar.gz".IO.extension: :5parts; # OUTPUT: «␤» 
 
# There is no 5-part extension, so we replaced nothing: 
say "foo.tar.gz".IO.extension: 'ZIP', :5parts; # OUTPUT: «"foo.tar.gz".IO␤» 
 
# Replacing a 0-part extension is just appending: 
say "foo.tar.gz".IO.extension: 'ZIP', :0parts; # OUTPUT: «"foo.tar.gz.ZIP".IO␤» 
 
# Replace 1-part of the extension, using '.' joiner 
say "...".IO.extension: 'tar'; # OUTPUT: «"...tar".IO␤» 
 
# Replace 1-part of the extension, using empty string joiner 
say "...".IO.extension: 'tar', :joiner(''); # OUTPUT: «"..tar".IO␤» 
 
# Remove 1-part extension; results in empty basename, so result is ".".IO 
say ".".IO.extension: ''; # OUTPUT: «".".IO␤»

method dirname

Defined as:

method dirname(IO::Path:D:)

Returns the directory name portion of the path object. That is, it returns the path excluding the volume and the base name. Unless the dirname consist of only the directory separator (i.e. it's the top directory), the trailing directory separator will not be included in the return value.

say IO::Path.new("/home/camelia/myfile.p6").dirname; # OUTPUT: «/home/camelia␤» 
say IO::Path::Win32.new("C:/home/camelia").dirname;  # OUTPUT: «/home␤» 
say IO::Path.new("/home").dirname;                   # OUTPUT: «/␤»

method volume

Defined as:

method volume(IO::Path:D:)

Returns the volume portion of the path object. On Unix system, this is always the empty string.

say IO::Path::Win32.new("C:\\Windows\\registry.ini").volume;    # OUTPUT: «C:␤»

method parts

Defined as:

method parts(IO::Path:D: --> Map:D)

Returns a Map with the keys volume, dirname, basename whose values are the same as available via methods .volume, .dirname, and .basename respectively.

say IO::Path::Win32.new("C:/rakudo/perl6.bat").parts.perl;
# OUTPUT: «Map.new((:basename("perl6.bat"),:dirname("/rakudo"),:volume("C:")))␤»

method perl

Defined as:

method perl(IO::Path:D: --> Str:D)

Returns a string that, when given passed through EVAL gives the original invocant back.

"foo/bar".IO.perl.say;
# OUTPUT: IO::Path.new("foo/bar", :SPEC(IO::Spec::Unix), :CWD("/home/camelia"))

Note that this string includes the value of the .CWD attribute that is set to $*CWD when the path object was created, by default.

method gist

Defined as:

method gist(IO::Path:D: --> Str:D)

Returns a string, part of which contains either the value of .absolute (if path is absolute) or .path. Note that no escaping of special characters is made, so e.g. "\b" means a path contains a backslash and letter "b", not a backspace.

say "foo/bar".IO;                       # OUTPUT: «"foo/bar".IO␤» 
say IO::Path::Win32.new: ｢C:\foo/bar\｣; # OUTPUT: «"C:\foo/bar\".IO␤»

method Str

Defined as:

method Str(IO::Path:D: --> Str)

Alias for IO::Path.path. In particular, note that default stringification of an IO::Path does NOT use the value of $.CWD attribute. To stringify while retaining full path information use .absolute or .relative methods.

method succ

Defined as:

method succ(IO::Path:D: --> IO::Path:D)

Returns a new IO::Path constructed from the invocant, with .basename changed by calling Str.succ on it.

"foo/file02.txt".IO.succ.say; # OUTPUT: «"foo/file03.txt".IO␤»

method open

Defined as:

method open(IO::Path:D: *%opts)

Opens the path as a file; the named options control the mode, and are the same as the open function accepts.

method pred

Defined as:

method pred(IO::Path:D: --> IO::Path:D)

Returns a new IO::Path constructed from the invocant, with .basename changed by calling Str.pred on it.

"foo/file02.txt".IO.pred.say; # OUTPUT: «"foo/file01.txt".IO␤»

method watch

Defined as:

method watch(IO::Path:D: --> Supply:D)

Equivalent to calling IO::Notification.watch-path with the invocant as the argument.

method is-absolute

Defined as:

method is-absolute(IO::Path:D: --> Bool)

Returns True if the path is an absolute path, and False otherwise.

"/foo".IO.is-absolute.say; # OUTPUT: «True␤» 
"bars".IO.is-absolute.say; # OUTPUT: «False␤»

Note that on Windows a path that starts with a slash or backslash is still considered absolute even if no volume was given, as it is absolute for that particular volume:

IO::Path::Win32.new("/foo"  ).is-absolute.say; # OUTPUT: «True␤» 
IO::Path::Win32.new("C:/foo").is-absolute.say; # OUTPUT: «True␤» 
IO::Path::Win32.new("C:foo" ).is-absolute.say; # OUTPUT: «False␤»

method is-relative

Defined as:

method is-relative(IO::Path:D: --> Bool)

Returns True if the path is a relative path, and False otherwise. Windows caveats for .is-absolute apply.

method absolute

Defined as:

multi method absolute(IO::Path:D: --> Str)
multi method absolute(IO::Path:D: $base --> Str)

Returns a new Str object that is an absolute path. If the invocant is not already an absolute path, it is first made absolute using $base as base, if it is provided, or the .CWD attribute the object was created with if it is not.

method relative

Defined as:

method relative(IO::Path:D: $base = $*CWD --> Str)

Returns a new Str object with the path relative to the $base. If $base is not provided, $*CWD is used in its place. If the invocant is not an absolute path, it's first made to be absolute using the .CWD attribute the object was created with, and then is made relative to $base.

method parent

Defined as:

multi method parent(IO::Path:D:)
multi method parent(IO::Path:D: UInt:D $level)

Returns the parent path of the invocant. Note that no actual filesystem access is made, so the returned parent is physical and not the logical parent of symlinked directories.

'/etc/foo'.IO.parent.say; # OUTPUT: «"/etc".IO␤» 
'/etc/..' .IO.parent.say; # OUTPUT: «"/etc".IO␤» 
'/etc/../'.IO.parent.say; # OUTPUT: «"/etc".IO␤» 
'./'      .IO.parent.say; # OUTPUT: «"..".IO␤» 
'foo'     .IO.parent.say; # OUTPUT: «".".IO␤» 
'/'       .IO.parent.say; # OUTPUT: «"/".IO␤» 
IO::Path::Win32.new('C:/').parent.say; # OUTPUT: «"C:/".IO␤»

If $level is specified, the call is equivalent to calling .parent() $level times:

say "/etc/foo".IO.parent(2) eqv "/etc/foo".IO.parent.parent; # OUTPUT: «True␤» 

method resolve

Defined as:

method resolve(IO::Path:D: :$completely --> IO::Path)

Returns a new IO::Path object with all symbolic links and references to the parent directory (..) resolved. This means that the filesystem is examined for each directory in the path, and any symlinks found are followed.

# bar is a symlink pointing to "/baz" 
my $io = "foo/./bar/..".IO.resolve;      # now "/" (the parent of "/baz")

If :$completely, which defaults to False, is set to a true value, the method will fail with X::IO::Resolve if it cannot completely resolve the path, otherwise, it will resolve as much as possible, and will merely perform cleanup of the rest of the path. The last part of the path does NOT have to exist to :$completely resolve the path.

NOTE: Currently (April 2017) this method doesn't work correctly on all platforms, e.g. Windows, since it assumes POSIX semantics.

routine dir

Defined as:

sub    dir(Cool $path = '.', Mu :$test = none('.', '..'))
method dir(IO::Path:D: Mu :$test = none('.', '..'))

Returns the contents of a directory as a lazy list of IO::Path objects representing relative paths, filtered by smartmatching their names (as strings) against the :test parameter.

Since the tests are performed against Str arguments, not IO, the tests are executed in the $*CWD, instead of the target directory. When testing against file test operators, this won't work:

dir('mydir', test => { .IO.d })

while this will:

dir('mydir', test => { "mydir/$_".IO.d })

NOTE: a dir call opens a directory for reading, which counts towards maximum per-process open files for your program. Be sure to exhaust returned Seq before doing something like recursively performing more dir calls. You can exhaust it by assigning to a @-sigiled variable or simply looping over it. Note how examples below push further dirs to look through into an Array, rather than immediately calling dir on them. See also IO::Dir module that gives you finer control over closing dir handles.

Examples:

# To iterate over the contents of the current directory: 
for dir() -> $file {
    say $file;
}
 
# As before, but include even '.' and '..' which are filtered out by 
# the default :test matcher: 
for dir(test => *) -> $file {
    say $file;
}
 
# To get the names of all .jpg and .jpeg files in the home directory of the current user: 
my @jpegs = $*HOME.dir: test => /:i '.' jpe?g $/;

An example program that lists all files and directories recursively:

sub MAIN($dir = '.') {
    my @todo = $dir.IO;
    while @todo {
        for @todo.pop.dir -> $path {
            say $path.Str;
            @todo.push: $path if $path.d;
        }
    }
}

A lazy way to find the first three files ending in ".p6" recursively starting from the current directory:

my @stack = '.'.IO;
my $perl-files = gather while @stack {
    with @stack.pop {
        when :d { @stack.append: .dir }
        .take when .extension.lc eq 'p6'
    }
}
.put for $perl-files[^3];

File test operators

For most file tests, you can do a smartmatch ~~ or you can call a method. You don't need to actually open a filehandle in the traditional way (although you can) to do a filetest. You can simply append .IO to the filename. For instance, here is how to check whether a file is readable using smartmatch:

'/path/to/file'.IO ~~ :r;

File tests include:

• :d (Directory)

• :e (Exists)

• :f (File)

• :l (Symbolic link)

• :r (Readable)

• :rw (Readable and writable)

• :rwx (Readable, writable and executable)

• :s (Size)

• :w (Writable)

• :x (Executable)

• :z (Zero size)

Smartmatching on Pairs can be used to perform multiple tests at once:

say :d & :x;                # OUTPUT: «all(d => True, x => True)␤» 
say '/tmp'.IO ~~ :d & :x;   # OUTPUT: «True␤» 
say '/'.IO    ~~ :d & :rw;  # OUTPUT: «False␤»

All of the above tests can be used as methods (without the colon), though method tests may throw X::IO::DoesNotExist as documented below. Three tests only exist as methods: accessed, changed and modified.

You can also perform file tests on an already opened filehandle by testing against its .path method. For example, given filehandle $fh:

$fh.path ~~ :r;
$fh.path.r;       # method form 

method e

Defined as:

method e(--> Bool:D)

Returns True if the invocant is a path that exists.

method d

Defined as:

method d(--> Bool:D)

Returns True if the invocant is a path that exists and is a directory. The method will fail with X::IO::DoesNotExist if the path points to a non-existent filesystem entity.

method f

Defined as:

method f(--> Bool:D)

Returns True if the invocant is a path that exists and is a file. The method will fail with X::IO::DoesNotExist if the path points to a non-existent filesystem entity.

method s

Defined as:

method s(--> Int:D)

Returns the file size in bytes. May be called on paths that are directories, in which case the reported size is dependent on the operating system. The method will fail with X::IO::DoesNotExist if the path points to a non-existent filesystem entity.

say $*EXECUTABLE.IO.s; # OUTPUT : «467␤»

method l

Defined as:

method l(--> Bool:D)

Returns True if the invocant is a path that exists and is a symlink. The method will fail with X::IO::DoesNotExist if the path points to a non-existent filesystem entity.

method r

Defined as:

method r(--> Bool:D)

Returns True if the invocant is a path that exists and is accessible. The method will fail with X::IO::DoesNotExist if the path points to a non-existent filesystem entity.

method w

Defined as:

method w(--> Bool:D)

Returns True if the invocant is a path that exists and is writable. The method will fail with X::IO::DoesNotExist if the path points to a non-existent filesystem entity.

method rw

Defined as:

method rw(--> Bool:D)

Returns True if the invocant is a path that exists and is readable and writable. The method will fail with X::IO::DoesNotExist if the path points to a non-existent filesystem entity.

method x

Defined as:

method x(--> Bool:D)

Returns True if the invocant is a path that exists and is executable. The method will fail with X::IO::DoesNotExist if the path points to a non-existent filesystem entity.

method rwx

Defined as:

method rwx(--> Bool:D)

Returns True if the invocant is a path that exists and is executable, readable, and writable. The method will fail with X::IO::DoesNotExist if the path points to a non-existent filesystem entity.

method z

Defined as:

method z(--> Bool:D)

Returns True if the invocant is a path that exists and has size of 0. May be called on paths that are directories, in which case the reported file size (and thus the result of this method) is dependent on the operating system. The method will fail with X::IO::DoesNotExist if the path points to a non-existent filesystem entity.

method sibling

Defined as:

method sibling(IO::Path:D: Str() $sibling --> IO::Path:D)

Allows to reference a sibling file or directory. Returns a new IO::Path based on the invocant, with the .basename changed to $sibling. The $sibling is allowed to be a multi-part path fragment; see also .add.

say '.bashrc'.IO.sibling: '.bash_aliases'; # OUTPUT: «.bash_aliases".IO␤» 
say '/home/camelia/.bashrc'.IO.sibling: '.bash_aliases';
# OUTPUT: «/home/camelia/.bash_aliases".IO␤» 
 
say '/foo/' .IO.sibling: 'bar';  # OUTPUT: «/bar".IO␤» 
say '/foo/.'.IO.sibling: 'bar';  # OUTPUT: «/foo/bar".IO␤»

method words

Defined as:

method words(IO::Path:D: :$chomp = True, :$enc = 'utf8', :$nl-in = ["\x0A", "\r\n"], |c --> Seq:D)

Opens the invocant and returns its words.

The behavior is equivalent to opening the file specified by the invocant, forwarding the :$chomp, :$enc, and :$nl-in arguments to IO::Handle.open, then calling IO::Handle.words on that handle, forwarding any of the remaining arguments to that method, and returning the resultant Seq.

NOTE: words are lazily read. The handle used under the hood is not closed until the returned Seq is fully reified, and this could lead to leaking open filehandles. It is possible to avoid leaking open filehandles using the $limit argument to cut down the Seq of words to be generated.

my %dict := bag 'my-file.txt'.IO.words;
say "Most common words: ", %dict.sort(-*.value).head: 5;

method lines

Defined as:

method lines(IO::Path:D: :$chomp = True, :$enc = 'utf8', :$nl-in = ["\x0A", "\r\n"], |c --> Seq:D)

Opens the invocant and returns its lines.

The behavior is equivalent to opening the file specified by the invocant, forwarding the :$chomp, :$enc, and :$nl-in arguments to IO::Handle.open, then calling IO::Handle.lines on that handle, forwarding any of the remaining arguments to that method, and returning the resultant Seq.

NOTE: the lines are ready lazily and the handle used under the hood won't get closed until the returned Seq is fully reified, so ensure it is, or you'll be leaking open filehandles. (TIP: use the $limit argument)

say "The file contains ",
  '50GB-file'.IO.lines.grep(*.contains: 'Perl').elems,
  " lines that mention Perl";
# OUTPUT: «The file contains 72 lines that mention Perl␤» 

routine slurp

Defined as:

multi method slurp(IO::Path:D: :$bin, :$enc)

Read all of the file's content and return it as either Buf, if :$bin is True, or if not, as Str decoded with :$enc encoding, which defaults to utf8. File will be closed afterwards. See &open for valid values for :$enc.

method spurt

Defined as:

method spurt(IO::Path:D: $data, :$enc, :$append, :$createonly)

Opens the file path for writing, and writes all of the $data into it. File will be closed, afterwards. Will fail if it cannot succeed for any reason. The $data can be any Cool type or any Blob type. Arguments are as follows:

• :$enc — character encoding of the data. Takes same values as :$enc in IO::Handle.open. Defaults to utf8. Ignored if $data is a Blob.

• :$append — open the file in append mode, preserving existing contents, and appending data to the end of the file.

• :$createonly — fail if the file already exists.

method chdir

Defined as:

multi method chdir(IO::Path:D: Str() $path, :$d = True, :$r, :$w, :$x)

DEPRECATION NOTICE: this method will be deprecated in 6.d language and removed in 6.e. Do not use it for new code. Instead, create a new path or use add method. For altering current working directory see &chdir and &*chdir subroutines.

Contrary to the name, the .chdir method does not change any directories, but merely concatenates the given $path to the invocant and returns the resultant IO::Path. Optional file tests can be performed by providing :d, :r, :w, or :x Bool named arguments; when set to True, they'll perform .d, .r, .w, and .x tests respectively. By default, only :d is set to True.

sub mkdir

Defined as:

method mkdir(IO::Path:D: Int() $mode = 0o777 --> IO::Path:D)

Creates a new directory, including its parent directories, as needed (similar to *nix utility mkdir with -p option). That is, mkdir "foo/bar/ber/meow" will create foo, foo/bar, and foo/bar/ber directories as well if they do not exist.

Returns the IO::Path object pointing to the newly created directory on success; fails with X::IO::Mkdir if directory cannot be created.

See also mode for explanation and valid values for $mode.

routine rmdir

Defined as:

sub    rmdir(*@dirs --> List:D)
method rmdir(IO::Path:D: --> True)

Remove the invocant, or in sub form, all of the provided directories in the given list, which can contain any Cool object. Only works on empty directories.

Method form returns True on success and returns a Failure of type X::IO::Rmdir if the directory cannot be removed (e.g. the directory is not empty, or the path is not a directory). Subroutine form returns a list of directories that were successfully deleted.

To delete non-empty directory, see rmtree in File::Directory::Tree module.

method chmod

Defined as:

method chmod(IO::Path:D: Int() $mode --> Bool)

Changes the POSIX permissions of a file or directory to $mode. Returns True on success; on failure, fails with X::IO::Chmod.

The mode is expected as an integer following the standard numeric notation, and is best written as an octal number:

'myfile'.IO.chmod(0o444);          # make a file read-only 
'somedir'.IO.chmod(0o777);         # set 0777 permissions on a directory 

Make sure you don't accidentally pass the intended octal digits as a decimal number (or string containing a decimal number):

'myfile'.IO.chmod:  '0444';        # BAD!!! (interpreted as mode 0o674) 
'myfile'.IO.chmod: '0o444';        # OK (an octal in a string) 
'myfile'.IO.chmod:  0o444;         # Also OK (an octal literal) 

routine rename

Defined as:

method rename(IO::Path:D: IO() $to, :$createonly = False --> Bool:D)
sub    rename(IO() $from, IO() $to, :$createonly = False --> Bool:D)

Renames a file or directory. Returns True on success; fails with X::IO::Rename if :$createonly is True and the $to path already exists or if the operation failed for some other reason.

Note: some renames will always fail, such as when the new name is on a different storage device. See also: move.

routine copy

Defined as:

method copy(IO::Path:D: IO() $to, :$createonly --> Bool:D)
sub    copy(IO() $from, IO() $to, :$createonly --> Bool:D)

Copies a file. Returns True on success; fails with X::IO::Copy if :$createonly is True and the $to path already exists or if the operation failed for some other reason, such as when $to and $from are the same file.

routine move

Defined as:

method move(IO::Path:D: IO() $to, :$createonly --> Bool:D)
sub    move(IO() $from, IO() $to, :$createonly --> Bool:D)

Copies a file and then removes the original. If removal fails, it's possible to end up with two copies of the file. Returns True on success; fails with X::IO::Move if :$createonly is True and the $to path already exists or if the operation failed for some other reason, such as when $to and $from are the same file.

To avoid copying, you can use rename, if the files are on the same storage device. It also works with directories, while move does not.

method Numeric

Defined as:

method Numeric(IO::Path:D: --> Numeric:D)

Coerces .basename to Numeric. Fails with X::Str::Numeric if base name is not numerical.

method Int

Defined as:

method Int(IO::Path:D: --> Int:D)

Coerces .basename to Int. Fails with X::Str::Numeric if base name is not numerical.

routine symlink

Defined as:

method symlink(IO::Path:D $target: IO() $link --> Bool:D)
sub    symlink(      IO() $target, IO() $link --> Bool:D)

Create a new symbolic link $link to existing $target. Returns True on success; fails with X::IO::Symlink if the symbolic link could not be created. If $target does not exist, creates a dangling symbolic link. To create a hard link, see link.

Note: on Windows, creation of symbolic links may require escalated privileges.

routine link

Defined as:

method link(IO::Path:D $target: IO() $link --> Bool:D)
sub    link(      IO() $target, IO() $link --> Bool:D)

Create a new hard link $link to existing $target. Returns True on success; fails with X::IO::Link if the hard link could not be created. To create a symbolic link, see symlink.

routine unlink

Defined as:

method unlink(IO::Path:D: --> True)
sub    unlink(*@filenames --> List:D)

Delete all specified ordinary files, links, or symbolic links for which there are privileges to do so. See rmdir to delete directories.

The subroutine form returns the names of all the files in the list, excluding those for which the filesystem raised some error; since trying to delete a file that does not exist does not raise any error at that level, this list will include the names of the files in the list that do not exist.

The method form returns True on success, or fails with X::IO::Unlink if the operation could not be completed. If the file to be deleted does not exist, the routine treats it as success.

'foo.txt'.IO.open(:w).close;
'bar'.IO.mkdir;
say unlink <foo.txt  bar  not-there.txt>; # OUTPUT: «[foo.txt not-there.txt]␤» 
# `bar` is not in output because it failed to delete (it's a directory) 
# `not-there.txt` is present. It never existed, so that's deemed a success. 
 
# Method form `fail`s: 
say .exception.message without 'bar'.IO.unlink;
# OUTPUT: «Failed to remove the file […] illegal operation on a directory␤» 

method IO

Defined as:

method IO(IO::Path:D: --> IO::Path)

Returns the invocant.

method SPEC

Defined as:

method SPEC(IO::Path:D: --> IO::Spec)

Returns the IO::Spec object that was (implicitly) specified at object creation time.

my $io = IO::Path.new("/bin/bash");
say $io.SPEC;                            # OUTPUT: «(Unix)␤» 
say $io.SPEC.dir-sep;                    # OUTPUT: «/␤»

File timestamp retrieval

There are also 3 methods for fetching the 3 timestamps of a file (inode), on Operating Systems where these are available:

method modified

Returns an Instant object indicating when the content of the file was last modified. Compare with changed.

say "path/to/file".IO.modified;          # Instant:1424089165 
say "path/to/file".IO.modified.DateTime; # 2015-02-16T12:18:50Z 

method accessed

Return an Instant object representing the timestamp when the file was last accessed. Note: depending on how the filesystem was mounted, the last accessed time may not update on each access to the file, but only on the first access after modifications.

say "path/to/file".IO.accessed;          # Instant:1424353577 
say "path/to/file".IO.accessed.DateTime; # 2015-02-19T13:45:42Z 

method changed

Returns an Instant object indicating the metadata of the file or directory was last changed (e.g. permissions, or files created/deleted in directory). Compare with modified.

say "path/to/file".IO.changed;           # Instant:1424089165 
say "path/to/file".IO.changed.DateTime;  # 2015-02-16T12:18:50Z 

File permissions retrieval

method mode

Return an IntStr object representing the POSIX permissions of a file. The Str part of the result is the octal representation of the file permission, like the form accepted by the chmod(1) utility.

say ~"path/to/file".IO.mode;  # e.g. '0644' 
say +"path/to/file".IO.mode;  # e.g. 420, where sprintf('%04o', 420) eq '0644' 

The result of this can be used in the other methods that take a mode as an argument.

"path/to/file1".IO.chmod("path/to/file2".IO.mode);  # will change the 
                                                    # permissions of file1 
                                                    # to be the same as file2 

Type Graph

Expand above chart

Routines supplied by class Cool

IO::Path inherits from class Cool, which provides the following routines:

(Cool) routine abs

Defined as:

sub abs(Numeric() $x)
method abs()

Coerces the invocant (or in the sub form, the argument) to Numeric and returns the absolute value (that is, a non-negative number).

say (-2).abs;       # OUTPUT: «2␤» 
say abs "6+8i";     # OUTPUT: «10␤»

(Cool) method conj

Defined as:

method conj()

Coerces the invocant to Numeric and returns the complex conjugate (that is, the number with the sign of the imaginary part negated).

say (1+2i).conj;        # OUTPUT: «1-2i␤»

(Cool) routine EVAL

Defined as:

method EVAL(*%_)

It calls the subroutine form with the invocant as the first argument, $code, passing along named args, if any.

(Cool) routine sqrt

Defined as:

sub sqrt(Numeric(Cool) $x)
method sqrt()

Coerces the invocant to Numeric (or in the sub form, the argument) and returns the square root, that is, a non-negative number that, when multiplied with itself, produces the original number.

say 4.sqrt;             # OUTPUT: «2␤» 
say sqrt(2);            # OUTPUT: «1.4142135623731␤»

(Cool) method sign

Defined as:

method sign()

Coerces the invocant to Numeric and returns its sign, that is, 0 if the number is 0, 1 for positive and -1 for negative values.

say 6.sign;             # OUTPUT: «1␤» 
say (-6).sign;          # OUTPUT: «-1␤» 
say "0".sign;           # OUTPUT: «0␤»

(Cool) method rand

Defined as:

method rand()

Coerces the invocant to Num and returns a pseudo-random value between zero and the number.

say 1e5.rand;           # OUTPUT: «33128.495184283␤»

(Cool) routine sin

Defined as:

sub sin(Numeric(Cool))
method sin()

Coerces the invocant (or in the sub form, the argument) to Numeric, interprets it as radians, returns its sine.

say sin(0);             # OUTPUT: «0␤» 
say sin(pi/4);          # OUTPUT: «0.707106781186547␤» 
say sin(pi/2);          # OUTPUT: «1␤»

Note that Raku is no computer algebra system, so sin(pi) typically does not produce an exact 0, but rather a very small floating-point number.

(Cool) routine asin

Defined as:

sub asin(Numeric(Cool))
method asin()

Coerces the invocant (or in the sub form, the argument) to Numeric, and returns its arc-sine in radians.

say 0.1.asin;               # OUTPUT: «0.10016742116156␤» 
say asin(0.1);              # OUTPUT: «0.10016742116156␤»

(Cool) routine cos

Defined as:

sub cos(Numeric(Cool))
method cos()

Coerces the invocant (or in sub form, the argument) to Numeric, interprets it as radians, returns its cosine.

say 0.cos;                  # OUTPUT: «1␤» 
say pi.cos;                 # OUTPUT: «-1␤» 
say cos(pi/2);              # OUTPUT: «6.12323399573677e-17␤»

(Cool) routine acos

Defined as:

sub acos(Numeric(Cool))
method acos()

Coerces the invocant (or in sub form, the argument) to Numeric, and returns its arc-cosine in radians.

say 1.acos;                 # OUTPUT: «0␤» 
say acos(-1);               # OUTPUT: «3.14159265358979␤»

(Cool) routine tan

Defined as:

sub tan(Numeric(Cool))
method tan()

Coerces the invocant (or in sub form, the argument) to Numeric, interprets it as radians, returns its tangent.

say tan(3);                 # OUTPUT: «-0.142546543074278␤» 
say 3.tan;                  # OUTPUT: «-0.142546543074278␤»

(Cool) routine atan

Defined as:

sub atan(Numeric(Cool))
method atan()

Coerces the invocant (or in sub form, the argument) to Numeric, and returns its arc-tangent in radians.

say atan(3);                # OUTPUT: «1.24904577239825␤» 
say 3.atan;                 # OUTPUT: «1.24904577239825␤»

(Cool) routine atan2

Defined as:

method atan2($y = 1e0)

Coerces self and argument to Numeric, using them to compute the two-argument arc-tangent in radians.

say 3.atan2;                # OUTPUT: «1.24904577239825␤» 
say ⅔.atan2(⅓);             # OUTPUT: «1.1071487177940904␤»

The first argument defaults to 1, so in the first case the function will return the angle θ in radians between a vector that goes from origin to the point (3, 1) and the x axis.

(Cool) routine sec

Defined as:

sub sec(Numeric(Cool))
method sec()

Coerces the invocant (or in sub form, its argument) to Numeric, interprets it as radians, returns its secant, that is, the reciprocal of its cosine.

say 45.sec;                 # OUTPUT: «1.90359440740442␤» 
say sec(45);                # OUTPUT: «1.90359440740442␤»

(Cool) routine asec

Defined as:

sub asec(Numeric(Cool))
method asec()

Coerces the invocant (or in sub form, its argument) to Numeric, and returns its arc-secant in radians.

say 1.asec;                 # OUTPUT: «0␤» 
say sqrt(2).asec;           # OUTPUT: «0.785398163397448␤»

(Cool) routine cosec

Defined as:

sub cosec(Numeric(Cool))
method cosec()

Coerces the invocant (or in sub form, its argument) to Numeric, interprets it as radians, returns its cosecant, that is, the reciprocal of its sine.

say 0.45.cosec;             # OUTPUT: «2.29903273150897␤» 
say cosec(0.45);            # OUTPUT: «2.29903273150897␤»

(Cool) routine acosec

Defined as:

sub acosec(Numeric(Cool))
method acosec()

Coerces the invocant (or in sub form, its argument) to Numeric, and returns its arc-cosecant in radians.

say 45.acosec;              # OUTPUT: «0.0222240516182672␤» 
say acosec(45)              # OUTPUT: «0.0222240516182672␤»

(Cool) routine cotan

Defined as:

sub cotan(Numeric(Cool))
method cotan()

Coerces the invocant (or in sub form, its argument) to Numeric, interprets it as radians, returns its cotangent, that is, the reciprocal of its tangent.

say 45.cotan;               # OUTPUT: «0.617369623783555␤» 
say cotan(45);              # OUTPUT: «0.617369623783555␤»

(Cool) routine acotan

Defined as:

sub acotan(Numeric(Cool))
method acotan()

Coerces the invocant (or in sub form, its argument) to Numeric, and returns its arc-cotangent in radians.

say 45.acotan;              # OUTPUT: «0.0222185653267191␤» 
say acotan(45)              # OUTPUT: «0.0222185653267191␤»

(Cool) routine sinh

Defined as:

sub sinh(Numeric(Cool))
method sinh()

Coerces the invocant (or in method form, its argument) to Numeric, and returns its Sine hyperbolicus.

say 1.sinh;                 # OUTPUT: «1.1752011936438␤» 
say sinh(1);                # OUTPUT: «1.1752011936438␤»

(Cool) routine asinh

Defined as:

sub asinh(Numeric(Cool))
method asinh()

Coerces the invocant (or in sub form, its argument) to Numeric, and returns its Inverse Sine hyperbolicus.

say 1.asinh;                # OUTPUT: «0.881373587019543␤» 
say asinh(1);               # OUTPUT: «0.881373587019543␤»

(Cool) routine cosh

Defined as:

sub cosh(Numeric(Cool))
method cosh()

Coerces the invocant (or in sub form, its argument) to Numeric, and returns its Cosine hyperbolicus.

say cosh(0.5);              # OUTPUT: «1.12762596520638␤»

(Cool) routine acosh

Defined as:

sub acosh(Numeric(Cool))
method acosh()

Coerces the invocant (or in sub form, its argument) to Numeric, and returns its Inverse Cosine hyperbolicus.

say acosh(45);              # OUTPUT: «4.4996861906715␤»

(Cool) routine tanh

Defined as:

sub tanh(Numeric(Cool))
method tanh()

Coerces the invocant (or in sub form, its argument) to Numeric, interprets it as radians and returns its Tangent hyperbolicus.

say tanh(0.5);              # OUTPUT: «0.46211715726001␤» 
say tanh(atanh(0.5));       # OUTPUT: «0.5␤»

(Cool) routine atanh

Defined as:

sub atanh(Numeric(Cool))
method atanh()

Coerces the invocant (or in sub form, its argument) to Numeric, and returns its Inverse tangent hyperbolicus.

say atanh(0.5);             # OUTPUT: «0.549306144334055␤»

(Cool) routine sech

Defined as:

sub sech(Numeric(Cool))
method sech()

Coerces the invocant (or in sub form, its argument) to Numeric, and returns its Secant hyperbolicus.

say 0.sech;                 # OUTPUT: «1␤»

(Cool) routine asech

Defined as:

sub asech(Numeric(Cool))
method asech()

Coerces the invocant (or in sub form, its argument) to Numeric, and returns its Inverse hyperbolic secant.

say 0.8.asech;              # OUTPUT: «0.693147180559945␤»

(Cool) routine cosech

Defined as:

sub cosech(Numeric(Cool))
method cosech()

Coerces the invocant (or in sub form, its argument) to Numeric, and returns its Hyperbolic cosecant.

say cosech(pi/2);           # OUTPUT: «0.434537208094696␤»

(Cool) routine acosech

Defined as:

sub acosech(Numeric(Cool))
method acosech()

Coerces the invocant (or in sub form, its argument) to Numeric, and returns its Inverse hyperbolic cosecant.

say acosech(4.5);           # OUTPUT: «0.220432720979802␤»

(Cool) routine cotanh

Defined as:

sub cotanh(Numeric(Cool))
method cotanh()

Coerces the invocant (or in sub form, its argument) to Numeric, and returns its Hyperbolic cotangent.

say cotanh(pi);             # OUTPUT: «1.00374187319732␤»

(Cool) routine acotanh

Defined as:

sub acotanh(Numeric(Cool))
method acotanh()

Coerces the invocant (or in sub form, its argument) to Numeric, and returns its Inverse hyperbolic cotangent.

say acotanh(2.5);           # OUTPUT: «0.423648930193602␤»

(Cool) routine cis

Defined as:

sub cis(Numeric(Cool))
method cis()

Coerces the invocant (or in sub form, its argument) to Numeric, and returns cos(argument) + i*sin(argument).

say cis(pi/4);              # OUTPUT: «0.707106781186548+0.707106781186547i␤»

(Cool) routine log

Defined as:

multi sub log(Numeric(Cool) $number, Numeric(Cool) $base?)
multi method log(Cool:D: Cool:D $base?)

Coerces the arguments (including the invocant in the method form) to Numeric, and returns its Logarithm to base $base, or to base e (Euler's Number) if no base was supplied (Natural logarithm). Returns NaN if $base is negative. Throws an exception if $base is 1.

say (e*e).log;              # OUTPUT: «2␤»

(Cool) routine log10

Defined as:

multi sub log10(Cool(Numeric))
multi method log10()

Coerces the invocant (or in the sub form, the invocant) to Numeric, and returns its Logarithm to base 10, that is, a number that approximately produces the original number when raised to the power of 10. Returns NaN for negative arguments and -Inf for 0.

say log10(1001);            # OUTPUT: «3.00043407747932␤»

(Cool) routine exp

Defined as:

multi sub exp(Cool:D $pow, Cool:D $base?)
multi method exp(Cool:D: Cool:D $base?)

Coerces the arguments (including the invocant in the method from) to Numeric, and returns $base raised to the power of the first number. If no $base is supplied, e (Euler's Number) is used.

say 0.exp;      # OUTPUT: «1␤» 
say 1.exp;      # OUTPUT: «2.71828182845905␤» 
say 10.exp;     # OUTPUT: «22026.4657948067␤»

(Cool) method unpolar

Defined as:

method unpolar(Numeric(Cool))

Coerces the arguments (including the invocant in the method form) to Numeric, and returns a complex number from the given polar coordinates. The invocant (or the first argument in sub form) is the magnitude while the argument (i.e. the second argument in sub form) is the angle. The angle is assumed to be in radians.

say sqrt(2).unpolar(pi/4);      # OUTPUT: «1+1i␤»

(Cool) routine round

Defined as:

multi sub round(Numeric(Cool))
multi method round(Cool:D: $unit = 1)

Coerces the invocant (or in sub form, its argument) to Numeric, and rounds it to the unit of $unit. If $unit is 1, rounds to the nearest integer.

say 1.7.round;          # OUTPUT: «2␤» 
say 1.07.round(0.1);    # OUTPUT: «1.1␤» 
say 21.round(10);       # OUTPUT: «20␤»

Always rounds up if the number is at mid-point:

say (−.5 ).round;       # OUTPUT: «0␤» 
say ( .5 ).round;       # OUTPUT: «1␤» 
say (−.55).round(.1);   # OUTPUT: «-0.5␤» 
say ( .55).round(.1);   # OUTPUT: «0.6␤»

Pay attention to types when using this method, as ending up with the wrong type may affect the precision you seek to achieve. For Real types, the type of the result is the type of the argument (Complex argument gets coerced to Real, ending up a Num). If rounding a Complex, the result is Complex as well, regardless of the type of the argument.

9930972392403501.round(1)      .perl.say; # OUTPUT: «9930972392403501␤» 
9930972392403501.round(1e0)    .perl.say; # OUTPUT: «9.9309723924035e+15␤» 
9930972392403501.round(1e0).Int.perl.say; # OUTPUT: «9930972392403500␤»

(Cool) routine floor

Defined as:

multi sub floor(Numeric(Cool))
multi method floor

Coerces the invocant (or in sub form, its argument) to Numeric, and rounds it downwards to the nearest integer.

say "1.99".floor;       # OUTPUT: «1␤» 
say "-1.9".floor;       # OUTPUT: «-2␤» 
say 0.floor;            # OUTPUT: «0␤»

(Cool) method fmt

Defined as:

method fmt($format = '%s')

Uses $format to return a formatted representation of the invocant; equivalent to calling sprintf with $format as format and the invocant as the second argument. The $format will be coerced to Stringy and defaults to '%s'.

For more information about formats strings, see sprintf.

say 11.fmt('This Int equals %03d');         # OUTPUT: «This Int equals 011␤» 
say '16'.fmt('Hexadecimal %x');             # OUTPUT: «Hexadecimal 10␤»

(Cool) routine ceiling

Defined as:

multi sub ceiling(Numeric(Cool))
multi method ceiling

Coerces the invocant (or in sub form, its argument) to Numeric, and rounds it upwards to the nearest integer.

say "1".ceiling;        # OUTPUT: «1␤» 
say "-0.9".ceiling;     # OUTPUT: «0␤» 
say "42.1".ceiling;     # OUTPUT: «43␤»

(Cool) routine truncate

Defined as:

multi sub truncate(Numeric(Cool))
multi method truncate()

Coerces the invocant (or in sub form, its argument) to Numeric, and rounds it towards zero.

say 1.2.truncate;       # OUTPUT: «1␤» 
say truncate -1.2;      # OUTPUT: «-1␤»

(Cool) routine ord

Defined as:

sub ord(Str(Cool))
method ord()

Coerces the invocant (or in sub form, its argument) to Str, and returns the Unicode code point number of the first code point.

say 'a'.ord;            # OUTPUT: «97␤»

The inverse operation is chr.

Mnemonic: returns an ordinal number

(Cool) method path

Defined as:

method path()

DEPRECATED. It's been deprecated as of the 6.d version. Will be removed in the next ones.

Stringifies the invocant and converts it to IO::Path object. Use the .IO method instead.

(Cool) routine chr

Defined as:

sub chr(Int(Cool))
method chr()

Coerces the invocant (or in sub form, its argument) to Int, interprets it as a Unicode code points, and returns a string made of that code point.

say '65'.chr;       # OUTPUT: «A␤»

The inverse operation is ord.

Mnemonic: turns an integer into a character.

(Cool) routine chars

Defined as:

multi sub chars(Cool $x)
multi sub chars(Str:D $x)
multi sub chars(str $x --> int)
method chars(--> Int:D)

Coerces the invocant (or in sub form, its argument) to Str, and returns the number of characters in the string. Please note that on the JVM, you currently get codepoints instead of graphemes.

say 'møp'.chars;    # OUTPUT: «3␤» 
say 'ã̷̠̬̊'.chars;     # OUTPUT: «1␤» 
say '👨‍👩‍👧‍👦🏿'.chars;    # OUTPUT: «1␤»

If the string is native, the number of chars will be also returned as a native int.

Graphemes are user visible characters. That is, this is what the user thinks of as a “character”.

Graphemes can contain more than one codepoint. Typically the number of graphemes and codepoints differs when Prepend or Extend characters are involved (also known as Combining characters), but there are many other cases when this may happen. Another example is \c[ZWJ] (Zero-width joiner).

You can check Grapheme_Cluster_Break property of a character in order to see how it is going to behave:

say ‘ã̷̠̬̊’.uniprops(‘Grapheme_Cluster_Break’); # OUTPUT: «(Other Extend Extend Extend Extend)␤» 
say ‘👨‍👩‍👧‍👦🏿’.uniprops(‘Grapheme_Cluster_Break’); # OUTPUT: «(E_Base_GAZ ZWJ E_Base_GAZ ZWJ E_Base_GAZ ZWJ E_Base_GAZ E_Modifier)␤»

You can read more about graphemes in the Unicode Standard, which Raku tightly follows, using a method called NFG, normal form graphemes for efficiently representing them.

(Cool) routine codes

Defined as:

sub codes(Str(Cool))
method codes()

Coerces the invocant (or in sub form, its argument) to Str, and returns the number of Unicode code points.

say 'møp'.codes;    # OUTPUT: «3␤»

The same result will be obtained with

say +'møp'.ords;    # OUTPUT: «3␤»

ords first obtains the actual codepoints, so there might be a difference in speed.

(Cool) routine flip

Defined as:

sub flip(Cool $s --> Str:D)
method flip()

Coerces the invocant (or in sub form, its argument) to Str, and returns a reversed version.

say 421.flip;       # OUTPUT: «124␤»

(Cool) routine trim

Defined as:

sub trim(Str(Cool))
method trim()

Coerces the invocant (or in sub form, its argument) to Str, and returns the string with both leading and trailing whitespace stripped.

my $stripped = '  abc '.trim;
say "<$stripped>";          # OUTPUT: «<abc>␤»

(Cool) routine trim-leading

Defined as:

sub trim-leading(Str(Cool))
method trim-leading()

Coerces the invocant (or in sub form, its argument) to Str, and returns the string with leading whitespace stripped.

my $stripped = '  abc '.trim-leading;
say "<$stripped>";          # OUTPUT: «<abc >␤»

(Cool) routine trim-trailing

Defined as:

sub trim-trailing(Str(Cool))
method trim-trailing()

Coerces the invocant (or in sub form, its argument) to Str, and returns the string with trailing whitespace stripped.

my $stripped = '  abc '.trim-trailing;
say "<$stripped>";          # OUTPUT: «<  abc>␤»

(Cool) routine lc

Defined as:

sub lc(Str(Cool))
method lc()

Coerces the invocant (or in sub form, its argument) to Str, and returns it case-folded to lower case.

say "ABC".lc;       # OUTPUT: «abc␤»

(Cool) routine uc

Defined as:

sub uc(Str(Cool))
method uc()

Coerces the invocant (or in sub form, its argument) to Str, and returns it case-folded to upper case (capital letters).

say "Abc".uc;       # OUTPUT: «ABC␤»

(Cool) routine fc

Defined as:

sub fc(Str(Cool))
method fc()

Coerces the invocant (or in sub form, its argument) to Str, and returns the result a Unicode "case fold" operation suitable for doing caseless string comparisons. (In general, the returned string is unlikely to be useful for any purpose other than comparison.)

say "groß".fc;       # OUTPUT: «gross␤»

(Cool) routine tc

Defined as:

sub tc(Str(Cool))
method tc()

Coerces the invocant (or in sub form, its argument) to Str, and returns it with the first letter case-folded to title case (or where not available, upper case).

say "abC".tc;       # OUTPUT: «AbC␤»

(Cool) routine tclc

Defined as:

sub tclc(Str(Cool))
method tclc()

Coerces the invocant (or in sub form, its argument) to Str, and returns it with the first letter case-folded to title case (or where not available, upper case), and the rest of the string case-folded to lower case.

say 'abC'.tclc;     # OUTPUT: «Abc␤»

(Cool) routine wordcase

Defined as:

sub wordcase(Str(Cool) $input, :&filter = &tclc, Mu :$where = True)
method wordcase(:&filter = &tclc, Mu :$where = True)

Coerces the invocant (or in sub form, the first argument) to Str, and filters each word that smartmatches against $where through the &filter. With the default filter (first character to upper case, rest to lower) and matcher (which accepts everything), this title-cases each word:

say "raku programming".wordcase;        # OUTPUT: «Raku Programming␤»

With a matcher:

say "have fun working on perl".wordcase(:where({ .chars > 3 }));
                                        # Have fun Working on Perl

With a customer filter too:

say "have fun working on perl".wordcase(:filter(&uc), :where({ .chars > 3 }));
                                        # HAVE fun WORKING on PERL

(Cool) routine samecase

Defined as:

sub samecase(Cool $string, Cool $pattern)
method samecase(Cool:D: Cool $pattern)

Coerces the invocant (or in sub form, the first argument) to Str, and returns a copy of $string with case information for each individual character changed according to $pattern.

Note: The pattern string can contain three types of characters, i.e. uppercase, lowercase and caseless. For a given character in $pattern its case information determines the case of the corresponding character in the result.

If $string is longer than $pattern, the case information from the last character of $pattern is applied to the remaining characters of $string.

say "raKu".samecase("A_a_"); # OUTPUT: «Raku␤» 
say "rAKU".samecase("Ab");   # OUTPUT: «Raku␤»

(Cool) routine uniprop

Defined as:

multi sub uniprop(Str:D, |c)
multi sub uniprop(Int:D $code)
multi sub uniprop(Int:D $code, Stringy:D $propname)
multi method uniprop(|c)

Returns the unicode property of the first character. If no property is specified returns the General Category. Returns a Bool for Boolean properties. A uniprops routine can be used to get the property for every character in a string.

say 'a'.uniprop;               # OUTPUT: «Ll␤» 
say '1'.uniprop;               # OUTPUT: «Nd␤» 
say 'a'.uniprop('Alphabetic'); # OUTPUT: «True␤» 
say '1'.uniprop('Alphabetic'); # OUTPUT: «False␤»

(Cool) sub uniprops

Defined as:

sub uniprops(Str:D $str, Stringy:D $propname = "General_Category")

Interprets the invocant as a Str, and returns the unicode property for each character as a Seq. If no property is specified returns the General Category. Returns a Bool for Boolean properties. Similar to uniprop, but for each character in the passed string.

(Cool) routine uniname

Defined as:

sub uniname(Str(Cool) --> Str)
method uniname(--> Str)

Interprets the invocant or first argument as a Str, and returns the Unicode codepoint name of the first codepoint of the first character. See uninames for a routine that works with multiple codepoints, and uniparse for the opposite direction.

# Camelia in Unicode 
say ‘»ö«’.uniname;
# OUTPUT: «"RIGHT-POINTING DOUBLE ANGLE QUOTATION MARK"␤» 
say "Ḍ̇".uniname; # Note, doesn't show "COMBINING DOT ABOVE" 
# OUTPUT: «"LATIN CAPITAL LETTER D WITH DOT BELOW"␤» 
 
# Find the char with the longest Unicode name. 
say (0..0x1FFFF).sort(*.uniname.chars)[*-1].chr.uniname;
# OUTPUT: ««ARABIC LIGATURE UIGHUR KIRGHIZ YEH WITH HAMZA ABOVE WITH ALEF MAKSURA INITIAL FORM␤»␤»

(Cool) routine uninames

Defined as:

sub uninames(Str:D)
method uninames()

Returns of a Seq of Unicode names for the all the codepoints in the Str provided.

say ‘»ö«’.uninames.perl;
# OUTPUT: «("RIGHT-POINTING DOUBLE ANGLE QUOTATION MARK", "LATIN SMALL LETTER O WITH DIAERESIS", "LEFT-POINTING DOUBLE ANGLE QUOTATION MARK").Seq␤»

Note this example, which gets a Seq where each element is a Seq of all the codepoints in that character.

say "Ḍ̇'oh".comb>>.uninames.perl;
# OUTPUT: «(("LATIN CAPITAL LETTER D WITH DOT BELOW", "COMBINING DOT ABOVE").Seq, ("APOSTROPHE",).Seq, ("LATIN SMALL LETTER O",).Seq, ("LATIN SMALL LETTER H",).Seq)␤»

See uniparse for the opposite direction.

(Cool) routine unimatch

Defined as:

multi sub unimatch(Str:D $str, |c)
multi unimatch(Int:D $code, Stringy:D $pvalname, Stringy:D $propname = $pvalname)

Checks if the given integer codepoint or the first letter of the string given have a unicode property equal to the value you give. If you supply the Unicode property to be checked it will only return True if that property matches the given value.

say unimatch 'A', 'Latin';           # OUTPUT: «True␤» 
say unimatch 'A', 'Latin', 'Script'; # OUTPUT: «True␤» 
say unimatch 'A', 'Ll';              # OUTPUT: «True␤»

(Cool) routine chop

Defined as:

sub chop(Str(Cool))
method chop()

Coerces the invocant (or in sub form, its argument) to Str, and returns it with the last character removed.

say 'perl'.chop;                        # OUTPUT: «per␤»

(Cool) routine chomp

Defined as:

sub chomp(Str(Cool))
method chomp()

Coerces the invocant (or in sub form, its argument) to Str, and returns it with the last character removed, if it is a logical newline.

say 'ab'.chomp.chars;                   # OUTPUT: «2␤» 
say "a\n".chomp.chars;                  # OUTPUT: «1␤»

(Cool) routine substr

Defined as:

sub substr(Str(Cool) $str, |c)
method substr(|c)

Coerces the invocant (or in the sub form, the first argument) to Str, and calls Str.substr with the arguments.

(Cool) routine substr-rw

Defined as:

multi method substr-rw(|) is rw
multi sub substr-rw(|) is rw

Coerces the invocant (or in the sub form, the first argument) to Str, and calls Str.substr-rw with the arguments.

(Cool) routine ords

Defined as:

sub ords(Str(Cool) $str)
method ords()

Coerces the invocant (or in the sub form, the first argument) to Str, and returns a list of Unicode codepoints for each character.

say "Camelia".ords;              # OUTPUT: «67 97 109 101 108 105 97␤» 
say ords 10;                     # OUTPUT: «49 48␤»

This is the list-returning version of ord. The inverse operation in chrs. If you are only interested in the number of codepoints, codes is a possibly faster option.

(Cool) routine chrs

Defined as:

sub chrs(*@codepoints --> Str:D)
method chrs()

Coerces the invocant (or in the sub form, the argument list) to a list of integers, and returns the string created by interpreting each integer as a Unicode codepoint, and joining the characters.

say <67 97 109 101 108 105 97>.chrs;   # OUTPUT: «Camelia␤»

This is the list-input version of chr. The inverse operation is ords.

(Cool) routine split

Defined as:

multi sub    split(  Str:D $delimiter, Str(Cool) $input, $limit = Inf, :$k, :$v, :$kv, :$p, :$skip-empty)
multi sub    split(Regex:D $delimiter, Str(Cool) $input, $limit = Inf, :$k, :$v, :$kv, :$p, :$skip-empty)
multi sub    split(@delimiters, Str(Cool) $input, $limit = Inf, :$k, :$v, :$kv, :$p, :$skip-empty)
multi method split(  Str:D $delimiter, $limit = Inf, :$k, :$v, :$kv, :$p, :$skip-empty)
multi method split(Regex:D $delimiter, $limit = Inf, :$k, :$v, :$kv, :$p, :$skip-empty)
multi method split(@delimiters, $limit = Inf, :$k, :$v, :$kv, :$p, :$skip-empty)

[1]

Coerces the invocant (or in the sub form, the second argument) to Str, and splits it into pieces based on delimiters found in the string.

If $delimiter is a string, it is searched for literally and not treated as a regex. You can also provide multiple delimiters by specifying them as a list; mixing Cool and Regex objects is OK.

say split(';', "a;b;c").perl;               # OUTPUT: «("a", "b", "c")␤» 
say split(';', "a;b;c", 2).perl;            # OUTPUT: «("a", "b;c").Seq␤» 
 
say split(';', "a;b;c,d").perl;             # OUTPUT: «("a", "b", "c,d")␤» 
say split(/\;/, "a;b;c,d").perl;            # OUTPUT: «("a", "b", "c,d")␤» 
say split(/<[;,]>/, "a;b;c,d").perl;        # OUTPUT: «("a", "b", "c", "d")␤» 
 
say split(['a', /b+/, 4], '1a2bb345').perl; # OUTPUT: «("1", "2", "3", "5")␤»

By default, split omits the matches, and returns a list of only those parts of the string that did not match. Specifying one of the :k, :v, :kv, :p adverbs changes that. Think of the matches as a list that is interleaved with the non-matching parts.

The :v interleaves the values of that list, which will be either Match objects, if a Regex was used as a matcher in the split, or Str objects, if a Cool was used as matcher. If multiple delimiters are specified, Match objects will be generated for all of them, unless all of the delimiters are Cool.

say 'abc'.split(/b/, :v);               # OUTPUT: «(a ｢b｣ c)␤» 
say 'abc'.split('b', :v);               # OUTPUT: «(a b c)␤»

:k interleaves the keys, that is, the indexes:

say 'abc'.split(/b/, :k);               # OUTPUT: «(a 0 c)␤»

:kv adds both indexes and matches:

say 'abc'.split(/b/, :kv);               # OUTPUT: «(a 0 ｢b｣ c)␤»

and :p adds them as Pairs, using the same types for values as :v does:

say 'abc'.split(/b/, :p);               # OUTPUT: «(a 0 => ｢b｣ c)␤» 
say 'abc'.split('b', :p);               # OUTPUT: «(a 0 => b c)␤»

You can only use one of the :k, :v, :kv, :p adverbs in a single call to split.

Note that empty chunks are not removed from the result list. For that behavior, use the :skip-empty named argument:

say ("f,,b,c,d".split: /","/             ).perl;  # OUTPUT: «("f", "", "b", "c", "d")␤» 
say ("f,,b,c,d".split: /","/, :skip-empty).perl;  # OUTPUT: «("f", "b", "c", "d")␤»

(Cool) routine lines

Defined as:

sub lines(Str(Cool))
method lines()

Coerces the invocant (and in sub form, the argument) to Str, decomposes it into lines (with the newline characters stripped), and returns the list of lines.

say lines("a\nb\n").join('|');          # OUTPUT: «a|b␤» 
say "some\nmore\nlines".lines.elems;    # OUTPUT: «3␤»

This method can be used as part of an IO::Path to process a file line-by-line, since IO::Path objects inherit from Cool, e.g.:

for 'huge-csv'.IO.lines -> $line {
    # Do something with $line 
}
 
# or if you'll be processing later 
my @lines = 'huge-csv'.IO.lines;

Without any arguments, sub lines operates on $*ARGFILES, which defaults to $*IN in the absence of any filenames.

To modify values in place use is copy to force a writable container.

for $*IN.lines -> $_ is copy { s/(\w+)/{$0 ~ $0}/; .say }

(Cool) method words

Defined as:

method words(Cool:D: |c)

Coerces the invocant (or first argument, if it is called as a subroutine) to Str, and returns a list of words that make up the string. Check Str.words for additional arguments and its meaning.

say <The quick brown fox>.words.join('|');     # OUTPUT: «The|quick|brown|fox␤» 
say <The quick brown fox>.words(2).join('|');  # OUTPUT: «The|quick␤» 

Cool is the base class for many other classes, and some of them, like Match, can be converted to a string. This is what happens in this case:

say ( "easy come, easy goes" ~~ m:g/(ea\w+)/).words(Inf);
# OUTPUT: «(easy easy)␤» 
say words( "easy come, easy goes" ~~ m:g/(ea\w+)/ , ∞);
# OUTPUT: «(easy easy)␤»

The example above illustrates two of the ways words can be invoked, with the first argument turned into invocant by its signature. Of course, Inf is the default value of the second argument, so in both cases (and forms) it can be simply omitted.

Only whitespace (including no-break space) counts as word boundaries

say <Flying on a Boeing 747>.words.join('|');  # OUTPUT: «Flying|on|a|Boeing|747␤»

In this case, "Boeing 747" includes a (visible only in the source) no-break space; words still splits the (resulting) Str on it, even if the original array only had 4 elements:

say <Flying on a Boeing 747>.join('|');        # OUTPUT: «Flying|on|a|Boeing 747␤»

Please see Str.words for more examples and ways to invoke it.

(Cool) routine comb

Defined as:

multi sub comb(Regex $matcher, Cool $input, $limit = *)
multi sub comb(Str $matcher, Cool $input, $limit = *)
multi sub comb(Int:D $size, Cool $input, $limit = *)
multi method comb(|c)

Returns a Seq of all (or if supplied, at most $limit) matches of the invocant (method form) or the second argument (sub form) against the Regex, string or defined number.

say "6 or 12".comb(/\d+/).join(", ");           # OUTPUT: «6, 12␤» 
say comb(/\d <[1..9]> /,(11..30)).join("--");
# OUTPUT: 
# «11--12--13--14--15--16--17--18--19--21--22--23--24--25--26--27--28--29␤»

The second statement exemplifies the first form of comb, with a Regex that excludes multiples of ten, and a Range (which is Cool) as $input. comb stringifies the Range before applying .comb on the resulting string. Check Str.comb for its effect on different kind of input strings. When the first argument is an integer, it indicates the (maximum) size of the chunks the input is going to be divided in

say comb(3,[3,33,333,3333]).join("*");  # OUTPUT: «3 3*3 3*33 *333*3␤»

In this case the input is a list, which after transformation to Str (which includes the spaces) is divided in chunks of size 3.

(Cool) method contains

Defined as:

method contains(Cool:D: |c)

Coerces the invocant to a Str, and calls Str.contains on it. Please refer to that version of the method for arguments and general syntax.

say 123.contains("2")# OUTPUT: «True␤»

Since Int is a subclass of Cool, 123 is coerced to a Str and then contains is called on it.

say (1,1, * + * … * > 250).contains(233)# OUTPUT: «True␤»

Seqs are also subclasses of Cool, and they are stringified to a comma-separated form. In this case we are also using an Int, which is going to be stringified also; "233" is included in that sequence, so it returns True. Please note that this sequence is not lazy; the stringification of lazy sequences does not include each and every one of their components for obvious reasons.

(Cool) routine index

Defined as:

multi sub index(Cool $s, Cool $needle, Cool $pos = 0)
method    index(Cool:D: |c)

Coerces the first two arguments (in method form, also counting the invocant) to a Str, and searches for $needle in the string $s starting from $startpos. It returns the offset into the string where $needle was found, and an undefined value if it was not found.

See the documentation in type Str for examples.

(Cool) routine rindex

Defined as:

multi sub    rindex(Str(Cool) $haystack, Str(Cool) $needle, Int(Cool) $startpos = $haystack.chars)
multi method rindex(Str(Cool) $haystack: Str(Cool) $needle, Int(Cool) $startpos = $haystack.chars)

Coerces the first two arguments (including the invocant in method form) to Str and $startpos to Int, and returns the last position of $needle in $haystack not after $startpos. Returns an undefined value if $needle wasn't found.

See the documentation in type Str for examples.

(Cool) method match

Defined as:

multi method match(Cool:D: $target, *%adverbs)

Coerces the invocant to Str and calls the method match on it.

(Cool) routine roots

Defined as:

multi sub roots(Numeric(Cool) $x, Int(Cool) $n)
multi method roots(Int(Cool) $n)

Coerces the first argument (and in method form, the invocant) to Numeric and the second ($n) to Int, and produces a list of $n Complex $n-roots, which means numbers that, raised to the $nth power, approximately produce the original number.

For example

my $original = 16;
my @roots = $original.roots(4);
say @roots;
 
for @roots -> $r {
    say abs($r ** 4 - $original);
}
 
# OUTPUT:«2+0i 1.22464679914735e-16+2i -2+2.44929359829471e-16i -3.67394039744206e-16-2i␤» 
# OUTPUT:«1.77635683940025e-15␤» 
# OUTPUT:«4.30267170434156e-15␤» 
# OUTPUT:«8.03651692704705e-15␤» 
# OUTPUT:«1.04441561648202e-14␤» 

(Cool) method match

Defined as:

method match(|)

Coerces the invocant to Stringy and calls Str.match.

(Cool) method subst

Defined as:

method subst(|)

Coerces the invocant to Stringy and calls Str.subst.

(Cool) method trans

Defined as:

method trans(|)

Coerces the invocant to Str and calls Str.trans

(Cool) method IO

Defined as:

method IO(--> IO::Path:D)

Coerces the invocant to IO::Path.

.say for '.'.IO.dir;        # gives a directory listing