class IO::Path

File or directory path

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.

method dirname

Defined as:

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.

method volume

Defined as:

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

method parts

Defined as:

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

method perl

Defined as:

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

method succ

Defined as:

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

method open

Defined as:

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:

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

method watch

Defined as:

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

method is-absolute

Defined as:

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

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:

method is-relative

Defined as:

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

Defined as:

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: 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: Returns the parent path of the invocant. Note that no filesystem access is made, so the returned parent is physical and not the logical parent of symlinked directories. If $level is specified, the call is equivalent to calling .parent() $level times: method resolve Defined as: Returns a new IO::Path object with all symbolic links and references to the parent directory (..) resolved. This means that the filesystem is examined for each directory in the path, and any symlinks found are followed. If :$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: 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:

while this will:

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:

An example program that lists all files and directories recursively:

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

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 if a file is readable using smartmatch: '/path/to/file'.IO ~~ :r

You can, of course, use an already opened filehandle. Here, using the filehandle $fh, is an example, using the method syntax for the file test: File tests include :e Exists :d Directory :f File :l Symbolic link :r Readable :w Writable :x Executable :s Size :z Zero size All of these tests can be used as methods (without the colon). Three tests, however exist only as methods:$fh.modified; $fh.accessed;$fh.changed;

method e

Defined as:

Returns True if the invocant is a path that exists.

TIP: use smartmatch with Pairs to perform multiple file tests.

method d

Defined as:

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.

TIP: use smartmatch with Pairs to perform multiple file tests.

method f

Defined as:

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.

TIP: use smartmatch with Pairs to perform multiple file tests.

method s

Defined as:

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.

TIP: use smartmatch with Pairs to perform multiple file tests.

method l

Defined as:

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.

TIP: use smartmatch with Pairs to perform multiple file tests.

method r

Defined as:

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.

TIP: use smartmatch with Pairs to perform multiple file tests.

method w

Defined as:

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.

TIP: use smartmatch with Pairs to perform multiple file tests.

method rw

Defined as:

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.

TIP: use smartmatch with Pairs to perform multiple file tests.

method x

Defined as:

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.

TIP: use smartmatch with Pairs to perform multiple file tests.

method rwx

Defined as:

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.

TIP: use smartmatch with Pairs to perform multiple file tests.

method z

Defined as:

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.

TIP: use smartmatch with Pairs to perform multiple file tests.

method sibling

Defined as:

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.

method words

Defined as:

Opens the invocant and returns its words.

The behaviour 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.

method lines

Defined as:

Opens the invocant and returns its lines.

The behaviour 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)

Defined as:

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. See &open for valid values for :$enc. method spurt Defined as: Opens the file path for writing, and writes all of the $data into it. 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.

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

method chdir

Defined as:

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.

routine rmdir

Defined as:

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 throws an exception 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.

Defined as:

Changes the POSIX permissions of a file or directory to $mode. Returns True on success; on failure, fails with X::IO::Chmod. The mode is expected as an integer following the standard numeric notation, and is best written as an octal number: Make sure you don't accidentally pass the intended octal digits as a decimal number (or string containing a decimal number): routine rename Defined as: Renames a file or directory. Returns True on success; fails with X::IO::Rename if :$createonly is True and the $to path already exists or if the operation failed for some other reason. Note: some renames will always fail, such as when the new name is on a different storage device. See also: move. routine copy Defined as: Copies a file. Returns True on success; fails with X::IO::Copy if :$createonly is True and the $to path already exists or if the operation failed for some other reason, such as when $to and $from are the same file. routine move Defined as: Copies a file and then removes the original. If removal fails, it's possible to end up with two copies of the file. Returns True on success; fails with X::IO::Move if :$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: Coerces .basename to Numeric. Fails with X::Str::Numeric if base name is not numerical. method Int Defined as: Coerces .basename to Int. Fails with X::Str::Numeric if base name is not numerical. Defined as: 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.

Defined as:

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.

Defined as:

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.

method IO

Defined as:

Returns the invocant.

method SPEC

Defined as:

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

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.

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.

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.

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.

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

Routines supplied by role IO

IO::Path does role IO, which provides the following routines:

Defined as:

Creates a new directory; see mode for explanation and valid values for $mode. Returns the IO::Path object pointing to the newly created directory on success; fails with X::IO::Mkdir if directory cannot be created. Also creates 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 if they do not exist, as well as foo/bar/ber/meow. (IO) sub chdir Defined as: Changes value of $*CWD variable to the provided $path, optionally ensuring the new path passes several file tests. NOTE: that this routine does NOT alter the process's current directory (see &*chdir). Returns IO::Path representing new $*CWD on success. On failure, returns Failure and leaves $*CWD untouched. The $path can be any object with an IO method that returns an IO::Path object. The available file tests are:

• :d — check .d returns True

• :r — check .r returns True

• :w — check .w returns True

• :x — check .x returns True

• By default, only :d test is performed.

Note that the following construct is a mistake:

Use indir instead.

(IO) sub &*chdir

Defined as:

Changes value of $*CWD variable to the provided $path and sets the process's current directory to the value of $path.absolute. NOTE: that in most cases, you want to use chdir routine instead. Returns IO::Path representing new $*CWD on success. On failure, returns Failure and leaves $*CWD untouched. The $path can be any object with an IO method that returns an IO::Path object.

Note that unlike regular chdir, there are no arguments to specify which file tests to perform.

Note that the following construct is a mistake:

Use the following, instead; or see indir if you do not need to change process's current directory:

Defined as:

Coerces all @filenames to IO::Path and calls IO::Path.chmod with $mode on them. Returns a List containing a subset of @filenames for which chmod was successfully executed. (IO) sub indir Defined as: Takes Callable &code and executes it after locally (to &code) changing $*CWD variable to an IO::Path object based on $path, optionally ensuring the new path passes several file tests. If $path is relative, it will be turned into an absolute path, even if an IO::Path object was given. NOTE: that this routine does NOT alter the process's current directory (see &*chdir). The $*CWD outside of the &code is not affected, even if &code explicitly assigns a new value to $*CWD.

Returns the return value of &code on success. On failure to successfully change $*CWD, returns Failure. WARNING: keep in mind that lazily evaluated things might end up NOT having the $*CWD set by indir in their dynamic scope by the time they're actually evaluated. Either ensure the generators have their $*CWD set or eagerly evaluate them before returning the results from indir: The routine's $path argument can be any object with an IO method that returns an IO::Path object. The available file tests are:

• :d — check .d returns True

• :r — check .r returns True

• :w — check .w returns True

• :x — check .x returns True

• By default, only :d test is performed.

Defined as:

(IO) sub prompt

Prints $msg to $*OUT handle if $msg was provided, then gets a line of input from $*IN handle. By default, this is equivalent to printing $msg to STDOUT, reading a line from STDIN, removing the trailing new line, and returning the resultant string. As of Rakudo 2018.08, prompt will create allomorphs for numeric values, equivalent to calling val prompt. In the code above, $age will be duck-typed to the allomorph IntStr if it's entered corectly as a number.

(Cool) routine log10

Defined as:

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.

(Cool) routine exp

Defined as:

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.

(Cool) method unpolar

Defined as:

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.

(Cool) routine round

Defined as:

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.

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

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.

(Cool) routine floor

Defined as:

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

(Cool) method fmt

Defined as:

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'

(Cool) routine ceiling

Defined as:

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

(Cool) routine truncate

Defined as:

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

(Cool) routine ord

Defined as:

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

The inverse operation is chr.

Mnemonic: returns an ordinal number

(Cool) method path

Defined as:

DEPRECATED. Existed only in the Rakudo implementation and isn't part of any language released. Will issue deprecation warnings in future language versions and eventually will be removed entirely.

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

(Cool) routine chr

Defined as:

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.

The inverse operation is ord.

Mnemonic: turns an integer into a character.

(Cool) routine chars

Defined as:

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.

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:

You can read more about graphemes in the Unicode Standard, which Perl 6 tightly follows, using a method called NFG, normal form graphemes for efficiently representing them.

(Cool) routine codes

Defined as:

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

The same result will be obtained with

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

(Cool) routine flip

Defined as:

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

(Cool) routine trim

Defined as:

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

Defined as:

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

(Cool) routine trim-trailing

Defined as:

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

(Cool) routine lc

Defined as:

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

(Cool) routine uc

Defined as:

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

(Cool) routine fc

Defined as:

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.)

(Cool) routine tc

Defined as:

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).

(Cool) routine tclc

Defined as:

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.

Defined as:

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: With a matcher: With a customer filter too: (Cool) routine samecase Defined as: 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.

(Cool) routine uniprop

Defined as:

Returns the unicode property of the first character. If no property is specified returns the General Category. Returns a Bool for Boolean properties.

(Cool) sub uniprops

Defined as:

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

(Cool) routine uniname

Defined as:

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.

(Cool) routine uninames

Defined as:

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

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

See uniparse for the opposite direction.

(Cool) routine unimatch

Defined as:

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.

(Cool) routine chop

Defined as:

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

(Cool) routine chomp

Defined as:

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.

(Cool) routine substr

Defined as:

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:

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:

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

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:

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.

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

(Cool) routine split

Defined as:

[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.

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 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: Coerces the invocant Str, and calls Str.contains on it. Please refer to that version of the method for arguments and general syntax. Since Int is a subclass of Cool, 123 is coerced to a Str and then contains is called on it. 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: 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: 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:

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

Defined as:

Uses $format to return a formatted representation of the invocant. For more information about formats strings, see sprintf. (Cool) routine roots Defined as: Coerces the first argument (and in method form, the invocant) to Numeric and the second ($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 (Cool) method match Defined as: Coerces the invocant to Stringy and calls Str.match. (Cool) method subst Defined as: Coerces the invocant to Stringy and calls Str.subst. (Cool) method trans Defined as: Coerces the invocant to Str and calls Str.trans (Cool) method IO Defined as: Coerces the invocant to IO::Path. (Cool) routine EVAL Defined as: If it is invoked as a method, it actually calls the subroutine form with invocant as the first argument, $code, passing along named args, if any; this coerces Cool $code to Str. If $code is a Blob, it'll be processed using the same encoding as the $lang compiler would: for perl6 $lang, uses utf-8; for Perl5, processes using the same rules as perl.

This works as-is with a literal string parameter. More complex input, such as a variable or string with embedded code, is illegal by default. This can be overridden in any of several ways:

In case the MONKEY-SEE-NO-EVAL pragma is not activated, the compiler will complain with a EVAL is a very dangerous function!!! exception. And it is essentially right, since that will run arbitrary code with the same permissions as the program. You should take care of cleaning the code that is going to pass through EVAL if you activate the MONKEY-SEE-NO-EVAL pragma.

Please note that you can interpolate to create routine names using quotation, as can be seen in this example or other ways to interpolate to create identifier names. This only works, however, for already declared functions and other objects and is thus safer to use.

Symbols in the current lexical scope are visible to code in an EVAL.

However, since the set of symbols in a lexical scope is immutable after compile time, an EVAL can never introduce symbols into the surrounding scope.

Furthermore, the EVAL is evaluated in the current package:

And also in the current language, meaning any added syntax is available:

An EVAL statement evaluates to the result of the last statement:

EVAL is also a gateway for executing code in other languages:

Defined as:

(Cool) routine printf

Defined as:

As a method, takes the object as a format using the same language as Str.sprintf; as a sub, its first argument will be the format string, and the rest of the arguments will be substituted in the format following the format conventions.

(Cool) routine sprintf

Defined as:

Formats and outputs a string, following the same language as Str.sprintf, using as such format either the object (if called in method form) or the first argument (if called as a routine)