NAME

Data::Dict - Hash-based dictionary object

SYNOPSIS

use Data::Dict;

# Manipulate dictionary
my $dictionary = Data::Dict->new(a => 1, b => 2, c => 3);
delete $dictionary->{b};
print join "\n", $dictionary->keys;

# Chain methods
$dictionary->slice(qw(a b))->grep(sub { defined $_[1] })->each(sub {
  my ($key, $value) = @_;
  print "$key: $value\n";
});

# Use the alternative constructor
use Data::Dict 'd';
use experimental 'signatures';
my $num_highest = d(%counts)->transform(sub ($k, $v) { ($k, $v+1) })->grep(sub ($k, $v) { $v > 5 })->size;

# Use Mojo::Collection for more chaining
d(%hash)->map_sorted_c(sub { join ':', @_ })->shuffle->join("\n")->say;

DESCRIPTION

Data::Dict is a hash-based container for dictionaries, with heavy inspiration from Mojo::Collection. Unless otherwise noted, all methods iterate through keys and values in default keys order, which is random but consistent until the hash is modified.

# Access hash directly to manipulate dictionary
my $dict = Data::Dict->new(a => 1, b => 2, c => 3);
$dict->{b} += 100;
print "$_\n" for values %$dict;

FUNCTIONS

d

my $dict = d(a => 1, b => 2);

Construct a new hash-based Data::Dict object. Exported on demand.

METHODS

new

my $dict = Data::Dict->new(a => 1, b => 2);

Construct a new hash-based Data::Dict object.

TO_JSON

Alias for "to_hash".

delete

my $deleted = $dict->delete(@keys);

Delete selected keys from the dictionary and return a new dictionary containing the deleted keys and values.

each

my @pairs = $dict->each;
$dict     = $dict->each(sub {...});

Evaluate callback for each pair in the dictionary, or return pairs as list of key/value arrayrefs if none has been provided. The callback will receive the key and value as arguments.

$dict->each(sub {
  my ($key, $value) = @_;
  print "$key: $value\n";
});

# values can be modified in place
$dict->each(sub { $_[1] = $_[0]x2 });

each_c

my $collection = $dict->each_c;

Create a new collection of key/value pairs as collections. Requires Mojo::Collection.

# print all keys and values
print $dict->each_c->flatten->join(' ');

each_sorted

my @pairs = $dict->each_sorted;
$dict     = $dict->each_sorted(sub {...});

As in "each", but the pairs are returned or the callback is called in sorted keys order.

each_sorted_c

my $collection = $dict->each_sorted_c;

As in "each_c", but the pairs are added to the collection in sorted keys order. Requires Mojo::Collection.

extract

my $extracted = $dict->extract(qr/foo/);
my $extracted = $dict->extract(sub {...});

Evaluate regular expression on each key, or call callback on each key/value pair in the dictionary, and remove all pairs that matched the regular expression, or for which the callback returned true. Return a new dictionary with the removed keys and values. The callback will receive the key and value as arguments.

my $high_numbers = $dict->extract(sub { $_[1] > 100 });

grep

my $new = $dict->grep(qr/foo/);
my $new = $dict->grep(sub {...});

Evaluate regular expression on each key, or call callback on each key/value pair in the dictionary, and return a new dictionary with all pairs that matched the regular expression, or for which the callback returned true. The callback will receive the key and value as arguments.

my $banana_dict = $dict->grep(qr/banana/);

my $fruits_dict = $dict->grep(sub { $_[1]->isa('Fruit') });

keys

my @keys = $dict->keys;
$dict    = $dict->keys(sub {...});

Evaluate callback for each key in the dictionary, or return all keys as a list if none has been provided. The key will be the first argument passed to the callback, and is also available as $_.

keys_c

my $collection = $dict->keys_c;

Create a new collection from all keys. Requires Mojo::Collection.

my $first_key = $dict->keys_c->first;

map

my @results = $dict->map(sub {...});

Evaluate callback for each key/value pair in the dictionary and return the results as a list. The callback will receive the key and value as arguments.

my @pairs = $dict->map(sub { [@_] });

my @values = $dict->map(sub { $_[1] });

map_c

my $collection = $dict->map_c(sub {...});

Evaluate callback for each key/value pair in the dictionary and create a new collection from the results. The callback will receive the key and value as arguments. Requires Mojo::Collection.

my $output = $dict->map_c(sub { "$_[0]: $_[1]" })->join("\n");

map_sorted

my @results = $dict->map_sorted(sub {...});

As in "map", but the callback is evaluated in sorted keys order.

map_sorted_c

my $collection = $dict->map_sorted_c(sub {...});

As in "map_c", but the callback is evaluated in sorted keys order. Requires Mojo::Collection.

size

my $size = $dict->size;

Number of keys in dictionary.

slice

my $new = $dict->slice(@keys);

Create a new dictionary with all selected keys.

print join ' ', d(a => 1, b => 2, c => 3)->slice('a', 'c')
  ->map_sorted(sub { join ':', @_ }); # a:1 c:3

tap

$dict = $dict->tap(sub {...});

Perform callback and return the dictionary object for further chaining, as in "tap" in Mojo::Base. The dictionary object will be the first argument passed to the callback, and is also available as $_.

to_collection

my $collection = $dict->to_collection;

Turn dictionary into even-sized collection of keys and values. Requires Mojo::Collection.

to_collection_sorted

my $collection = $dict->to_collection_sorted;

Turn dictionary into even-sized collection of keys and values in sorted keys order. Requires Mojo::Collection.

to_hash

my $hash = $dict->to_hash;

Turn dictionary into hash reference.

transform

my $new = $dict->transform(sub {...});

Evaluate callback for each key/value pair in the dictionary and create a new dictionary from the returned keys and values (assumed to be an even-sized key/value list). The callback will receive the key and value as arguments.

my $reversed = $dict->transform(sub { ($_[1], $_[0]) });

my $doubled = $dict->transform(sub {
  my ($k, $v) = @_;
  return ($k => $v, ${k}x2 => $v);
});

values

my @values = $dict->values;
$dict      = $dict->values(sub {...});

Evaluate callback for each value in the dictionary, or return all values as a list if none has been provided. The value will be the first argument passed to the callback, and is also available as $_.

# values can be modified in place
$dict->values(sub { $_++ });

values_c

my $collection = $dict->values_c;

Create a new collection from all values. Requires Mojo::Collection.

my @shuffled_values = $dict->values_c->shuffle->each;

BUGS

Report any issues on the public bugtracker.

AUTHOR

Dan Book <dbook@cpan.org>

COPYRIGHT AND LICENSE

This software is Copyright (c) 2018 by Dan Book.

This is free software, licensed under:

The Artistic License 2.0 (GPL Compatible)

SEE ALSO

Mojo::Collection