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Catmandu-1.2022
River stage two • 78 direct dependents • 84 total dependents
/ Catmandu::Util

NAME

Catmandu::Util - A collection of utility functions

SYNOPSIS

use Catmandu::Util qw(:string);

$str = trim($str);

FUNCTIONS

IO functions

use Catmandu::Util qw(:io);
io($io, %opts)

Takes a file path, glob, glob reference, scalar reference or IO::Handle object and returns an opened IO::Handle object.

my $fh = io '/path/to/file';

my $fh = io *STDIN;

my $fh = io \*STDOUT, mode => 'w', binmode => ':crlf';

my $write_cb = sub { my $str = $_[0]; ... };

my $fh = io $write_cb, mode => 'w';

my $scalar = "";
my $fh = io \$scalar, mode => 'w';
$fh->print("some text");

Options are:

mode

Default is "r".

binmode

Default is ":encoding(UTF-8)".

encoding

Alias for binmode.

read_file($path);

[deprecated]: use tools like Path::Tiny instead.

Reads the file at $path into a string.

my $str = read_file('/path/to/file.txt');

Throws a Catmandu::Error on failure.

read_io($io)

Reads an IO::Handle into a string.

my $str = read_file($fh);
write_file($path, $str);

[deprecated]: use tools like use tools like File::Slurp::Tiny instead.

Writes the string $str to a file at $path.

write_file('/path/to/file.txt', "contents");

Throws a Catmandu::Error on failure.

read_yaml($path);

Reads the YAML file at $path into a Perl hash.

my $cfg = read_yaml($path);

Dies on failure reading the file or parsing the YAML.

read_json($path);

Reads the JSON file at $path into a Perl hash.

my $cfg = read_json($path);

Dies on failure reading the file or parsing the JSON.

join_path(@path);

Joins relative paths into an absolute path.

join_path('/path/..', './to', 'file.txt');
# => "/to/file.txt"
normalize_path($path);

Normalizes a relative path to an absolute path.

normalize_path('/path/../to/./file.txt');
# => "/to/file.txt"
segmented_path($path);
my $id = "FB41144C-F0ED-11E1-A9DE-61C894A0A6B4";
segmented_path($id, segment_size => 4);
# => "FB41/144C/F0ED/11E1/A9DE/61C8/94A0/A6B4"
segmented_path($id, segment_size => 2, base_path => "/files");
# => "/files/FB/41/14/4C/F0/ED/11/E1/A9/DE/61/C8/94/A0/A6/B4"
content_type($filename);

Guess the content type of a file name.

content_type("book.pdf");
# => "application/pdf"

Hash functions

use Catmandu::Util qw(:hash);

A collection of functions that operate on hash references.

hash_merge($hash1, $hash2, ... , $hashN)

Merge <hash1> through <hashN>, with the nth-most (rightmost) hash taking precedence. Returns a new hash reference representing the merge.

hash_merge({a => 1}, {b => 2}, {a => 3});
# => { a => 3 , b => 2}

Array functions

use Catmandu::Util qw(:array);

A collection of functions that operate on array references.

array_exists($array, $index)

Returns 1 if $index is in the bounds of $array

array_exists(["a", "b"], 2);
# => 0
array_exists(["a", "b"], 1);
# => 1
array_group_by($array, $key)
my $list = [{color => 'black', id => 1},
            {color => 'white', id => 2},
            {id => 3},
            {color => 'black', id => 4}];
array_group_by($list, 'color');
# => {black => [{color => 'black', id => 1}, {color => 'black', id => 4}],
#     white => [{color => 'white', id => 2}]}
array_pluck($array, $key)
my $list = [{id => 1}, {}, {id => 3}];
array_pluck($list, 'id');
# => [1, undef, 3]
array_to_sentence($array)
array_to_sentence($array, $join)
array_to_sentence($array, $join, $join_last)
array_to_sentence([1,2,3]);
# => "1, 2 and 3"
array_to_sentence([1,2,3], ",");
# => "1,2 and 3"
array_to_sentence([1,2,3], ",", " & ");
# => "1,2 & 3"
array_sum($array)
array_sum([1,2,3]);
# => 6
array_includes($array, $val)

Returns 1 if $array includes a value that is deeply equal to $val, 0 otherwise. Comparison is done with is_same().

array_includes([{color => 'black'}], {color => 'white'});
# => 0
array_includes([{color => 'black'}], {color => 'black'});
# => 1
array_any($array, \&sub)
array_any(["green", "blue"], sub { my $color = $_[0]; $color eq "blue" });
# => 1
array_rest($array)

Returns a copy of $array without the head.

array_rest([1,2,3,4]);
# => [2,3,4]
array_rest([1]);
# => []
array_uniq($array)

Returns a copy of $array with all duplicates removed.

array_split($array | $string)

Returns $array or a new array by splitting $string at commas.

String functions

use Catmandu::Util qw(:string);
as_utf8($str)

Returns a copy of $str flagged as UTF-8.

trim($str)

Returns a copy of $str with leading and trailing whitespace removed.

capitalize($str)

Equivalent to ucfirst lc as_utf8 $str.

Is functions

use Catmandu::Util qw(:is);

is_number(42) ? "it's numeric" : "it's not numeric";

is_maybe_hash_ref({});
# => 1
is_maybe_hash_ref(undef);
# => 1
is_maybe_hash_ref([]);
# => 0

A collection of predicate functions that test the type or value of argument $val. Each function (except is_same() and is_different) also has a maybe variant that also tests true if $val is undefined. Returns 1 or 0.

is_invocant($val)
is_maybe_invocant($val)

Tests if $val is callable (is an existing package or blessed object).

is_able($val, @method_names)
is_maybe_able($val, @method_names)

Tests if $val is callable and has all methods in @method_names.

is_instance($val, @class_names)
is_maybe_instance($val, @class_names)

Tests if $val is a blessed object and an instance of all the classes in @class_names.

is_ref($val)
is_maybe_ref($val)

Tests if $val is a reference. Equivalent to ref $val ? 1 : 0.

is_scalar_ref($val)
is_maybe_scalar_ref($val)

Tests if $val is a scalar reference.

is_array_ref($val)
is_maybe_array_ref($val)

Tests if $val is an array reference.

is_hash_ref($val)
is_maybe_hash_ref($val)

Tests if $val is a hash reference.

is_code_ref($val)
is_maybe_code_ref($val)

Tests if $val is a subroutine reference.

is_regex_ref($val)
is_maybe_regex_ref($val)

Tests if $val is a regular expression reference generated by the qr// operator.

is_glob_ref($val)
is_maybe_glob_ref($val)

Tests if $val is a glob reference.

is_value($val)
is_maybe_value($val)

Tests if $val is a real value (defined, not a reference and not a glob.

is_string($val)
is_maybe_string($val)

Tests if $val is a non-empty string. Equivalent to is_value($val) && length($val) > 0.

is_number($val)
is_maybe_number($val)

Tests if $val is a number.

is_integer($val)
is_maybe_integer($val)

Tests if $val is an integer.

is_natural($val)
is_maybe_natural($val)

Tests if $val is a non-negative integer. Equivalent to is_integer($val) && $val >= 0.

is_positive($val)
is_maybe_positive($val)

Tests if $val is a positive integer. Equivalent to is_integer($val) && $val >= 1.

is_float($val)
is_maybe_float($val)

Tests if $val is a floating point number.

is_same($val, $other_val)

Tests if $val is deeply equal to $other_val.

is_different($val, $other_val)

The opposite of is_same().

Check functions

use Catmandu::Util qw(:check);

check_hash_ref({color => 'red'});
# => {color => 'red'}
check_hash_ref([]);
# dies

A group of assert functions similar to the :is group, but instead of returning true or false they return their argument or die.

check_invocant($val)
check_maybe_invocant($val)
check_able($val, @method_names)
check_maybe_able($val, @method_names)
check_instance($val, @class_names)
check_maybe_instance($val, @class_names)
check_ref($val)
check_maybe_ref($val)
check_scalar_ref($val)
check_maybe_scalar_ref($val)
check_array_ref($val)
check_maybe_array_ref($val)
check_hash_ref($val)
check_maybe_hash_ref($val)
check_code_ref($val)
check_maybe_code_ref($val)
check_regex_ref($val)
check_maybe_regex_ref($val)
check_glob_ref($val)
check_maybe_glob_ref($val)
check_value($val)
check_maybe_value($val)
check_string($val)
check_maybe_string($val)
check_number($val)
check_maybe_number($val)
check_integer($val)
check_maybe_integer($val)
check_natural($val)
check_maybe_natural($val)
check_positive($val)
check_maybe_positive($val)
check_float($val)
check_maybe_float($val)
check_same($val, $other_val)
check_different($val, $other_val)

Human output functions

use Catmandu::Util qw(:human);
human_number($num)

Insert a comma a 3-digit intervals to make $num more readable. Only works with integers for now.

human_number(64354);
# => "64,354"
human_byte_size($size)
human_byte_size(64);
# => "64 bytes"
human_byte_size(10005000);
# => "10.01 MB"
human_content_type($content_type)
human_content_type($content_type, $default)
human_content_type('application/x-dos_ms_excel');
# => "Excel"
human_content_type('application/zip');
# => "ZIP archive"
human_content_type('foo/x-unknown');
# => "foo/x-unknown"
human_content_type('foo/x-unknown', 'Unknown');
# => "Unknown"

XML functions

use Catmandu::Util qw(:xml);
xml_declaration()

Returns qq(<?xml version="1.0" encoding="UTF-8"?>\n).

xml_escape($str)

Returns an XML escaped copy of $str.

Miscellaneous functions

require_package($pkg)
require_package($pkg, $namespace)

Load package $pkg at runtime with require and return it's full name.

my $pkg = require_package('File::Spec');
my $dir = $pkg->tmpdir();

require_package('Util', 'Catmandu');
# => "Catmandu::Util"
require_package('Catmandu::Util', 'Catmandu');
# => "Catmandu::Util"

Throws a Catmandu::Error on failure.

use_lib(@dirs)

Add directories to @INC at runtime.

Throws a Catmandu::Error on failure.

pod_section($package_or_file, $section [, @options] )

Get documentation of a package for a selected section. Additional options are passed to Pod::Usage.

now($format)

Returns the current datetime as a string. $formatcan be any strftime format. There are also 2 builtin formats, iso_date_time and iso_date_time_millis. iso_date_time is equivalent to %Y-%m-%dT%H:%M:%SZ. iso_date_time_millis is the same, but with added milliseconds.

now('%Y/%m/%d');
now('iso_date_time_millis');

The default format is iso_date_time;