NAME

List::Rubyish - Array iterator like the Ruby

SYNOPSIS

my $array_ref = [
  {name => 'jkondo'},
  {name => 'cinnamon'}
];
my $list = List::Rubyish->new($array_ref);

$list->size;              #=> 2
my $first = $list->shift; #=> {name => 'jkondo'}
$list->push($first);      #=> [{name => 'cinnamon'}, {name => 'jkondo'}];

# List::Rubyish provides much more useful methods. For more
# details, see the sections below.

OVERVIEW

DBIx::MoCo::List is very useful, However installation is complex.

List::Rubyish was made in order to enable use of DBIx::MoCo::List independently.

METHODS

dump ()

Dump the content of $self using Data::Dumper.

push ( @array )

unshift ( @array )

Sets the argument into $self, a refernce to an array blessed by List::Rubyish, like the same name functions provided by Perl core, then returns a List::Rubyish object.

my $list = List::Rubyish->new([qw(1 2 3)]);
$list->push(4, 5); #=> [1, 2, 3, 4, 5]
$list->unshift(0); #=> [0, 1, 2, 3, 4, 5]

concat ( \@array )

prepend ( \@array )

They're almost the same as push()/unshift() described above except that the argument shoud be a reference to an array.

my $list = List::Rubyish->new([1, 2, 3]);
$list->concat([4, 5]); #=> [1, 2, 3, 4, 5]
$list->prepend([0]);   #=> [0, 1, 2, 3, 4, 5]

shift ()

pop ()

Pulls out the first/last element from $self, a refernce to an array blessed by List::Rubyish, then returns it like the same name functions in Perl core.

$list = List::Rubyish->new([1, 2, 3]);
$list->shift; #=> 1
$list->pop;   #=> 3
$list->dump   #=> [2]

first ()

last ()

Returns the first/last element of $self, a refernce to an array blessed by List::Rubyish. These methods aren't destructive contrary to shift()/pop() method.

$list = List::Rubyish->new([1, 2, 3]);
$list->first; #=> 1
$list->last;  #=> 3
$list->dump   #=> [1, 2, 3]

slice ( $start, $end )

Returns the elements whose indexes are between $start and $end as a List::Rubyish object.

$list = List::Rubyish->new([qw(1 2 3 4)]);
$list->slice(1, 2) #=> [2, 3]

zip ( \@array1, \@array2, ... )

Bundles up the elements in each arguments into an array or a List::Rubyish object along with the context.

my $list = List::Rubyish->new([1, 2, 3]);
$list->zip([4, 5, 6], [7, 8, 9]);
    #=> [[1, 4, 7], [2, 5, 8], [3, 6, 9]]

# When the numbers of each list are different...
$list = List::Rubyish->new([1, 2, 3]);
$list->zip([4, 5], [7, 8, 9]);
    #=> [[1, 4, 7], [2, 5, 8], [3, undef, 9]]

my $list   = List::Rubyish->new([1, 2]);
$list->zip([4, 5], [7, 8, 9]);
    #=> [[1, 4, 7], [2, 5, 8]]

delete ( $value, $code )

Deletes the same values as $value in $self, a refernce to an array blessed by List::Rubyish, and returns the value if found. If the value is not found in $self and $code is passed in, the code is executed using the value as an argument to find the value to be deleted.

$list = List::Rubyish->new([1, 2, 3, 2, 1]);
$list->delete(2); #=> 2
$list->dump       #=> [1, 3, 1]

delete_at ( $pos )

Deletes the element at $pos and returns it.

$list = List::Rubyish->new([1, 2, 3, 2, 1]);
$list->delete_at(3); #=> 2
$list->dump          #=> [1, 2, 3, 1]

delete_if ( $code )

Deletes the elements if $code returns true value with each element as an argument.

$list = List::Rubyish->new([1, 2, 3, 4]);
$list->delete_if(sub { ($_ % 2) == 0) });
$list->dump #=> [1, 3]

inject ( $result, $code )

Executes folding calculation using $code through each element and returns the result.

$list = List::Rubyish->new([1, 2, 3, 4]);
$list->inject(0, sub { $_[0] + $_[1] }); #=> 10

join ( $delimiter )

Joins all the elements by $delimiter.

$list = List::Rubyish->new([0 1 2 3]);
$list->join(', ') #=> '0, 1, 2, 3'

each_index ( $code )

Executes $code with each index of $self, a refernce to an array blessed by List::Rubyish.

$list = List::Rubyish->new([1, 2, 3]);
$list->each_index(sub { do_something($_) });

each ( $code )

Executes $code with each value of $self, a refernce to an array blessed by List::Rubyish.

$list = List::Rubyish->new([1, 2, 3]);
$list->each(sub { do_something($_) });

collect ( $code )

Executes $code with each element of $self, a refernce to an array blessed by List::Rubyish using CORE::map() and returns the results as a list or List::Rubyish object along with the context.

$list = List::Rubyish->new([1, 2, 3]);
$list->map(sub { $_ * 2 }); #=> [2, 4, 6]

map ( $code )

An alias of collect() method described above.

grep ( $code )

Executes $code with each element of $self, a refernce to an array blessed by List::Rubyish using CORE::grep() and returns the results as a list or List::Rubyish object along with the context.

$list = List::Rubyish->new([qw(1 2 3 4)]);
$list->grep(sub { ($_ % 2) == 0 }); #=> [2, 4]

find ( $code )

Returns the first value found in $self, a refernce to an array blessed by List::Rubyish, as a result of $code..

$list = List::Rubyish->new([1, 2, 3, 4]);
$list->find(sub { ($_ % 2) == 0 }); #=> 2

select ( $code )

Returns the values found in $self, a refernce to an array blessed by List::Rubyish, as a result of $code..

$list = List::Rubyish->new([1, 2, 3, 4]);
$list->select(sub { ($_ % 2) == 0 }); #=> 2, 4

index_of ( $arg )

Returns index of given target or given code returns true.

$list = List::Rubyish->new([qw(foo bar baz)]);
$list->index_of('bar');                  #=> 1
$list->index_of(sub { shift eq 'bar' }); #=> 1

sort ( $code )

Sorts out each element and returns the result as a list or List::Rubyish object along with the context.

$list = List::Rubyish->new([qw(3 2 4 1]);
$list->sort;                          #=> [1, 2, 3, 4]
$list->sort(sub { $_[1] <=> $_[0] }); #=> [4, 3, 2, 1]

sort_by ( $code, $cmp )

Sorts out each element with Schwartzian transform returns the result as a list or List::Rubyish object along with the context.

$list = List::Rubyish->new([ [3], [2], [4], [1]]);
$list->sort_by(sub { $_->[0] }); #=> [[1], [2], [3], [4]]
$list->sort_by(sub { $_->[0] }, sub { $_[1} <=> $_[0] } ); #=> [[4], [3], [2], [1]]

compact ()

Eliminates undefined values in $self, a refernce to an array blessed by List::Rubyish.

$list = List::Rubyish->new([1, 2, undef, 3, undef, 4]);
$list->compact; #=> [1, 2, 3, 4]

length ()

Returns the length of $self, a refernce to an array blessed by List::Rubyish.

$list = List::Rubyish->new([qw(1 2 3 4)]);
$list->length; #=> 4

size ()

An alias of length() method described above.

flatten ()

Returns a list or List::Rubyish object which is recursively flattened out.

$list = List::Rubyish->new([1, [2, 3, [4], 5]]);
$list->flattern; #=> [1, 2, 3, 4, 5]

is_empty ()

Returns true if $self, a refernce to an array blessed by List::Rubyish, is empty.

uniq ()

Uniquifies the elements in $self, a refernce to an array blessed by List::Rubyish, and returns the result.

$list = List::Rubyish->new([1, 2, 2, 3, 3, 4])
$list->uniq; #=> [1, 2, 3, 4]

reduce ( $code )

Reduces the list by $code.

# finds the maximum value
$list = List::Rubyish->new([4, 1, 3, 2])
$list->reduce(sub { $_[0] > $_[1] ? $_[0] : $_[1] }); #=> 4

See List::Util to get to know about details of reduce().

reverse ()

Returns an reversely ordered $self, a refernce to an array blessed by List::Rubyish.

$list = List::Rubyish->new([4, 1, 3, 2])
$list->reverse; #=> [2, 3, 1, 4]

dup ()

Returns a duplicated $self, a refernce to an array blessed by List::Rubyish.

sum ()

Returns the sum of each element in $self, a refernce to an array blessed by List::Rubyish.

$list = List::Rubyish->new([1, 2, 3, 4]);
$list->sum; #=> 10

SEE ALSO

DBIx::MoCo::List, List::Util, List::MoreUtils, http://github.com/naoya/list-rubylike, http://d.hatena.ne.jp/naoya/20080419/1208579525, http://www.ruby-lang.org/ja/man/html/Enumerable.html

AUTHOR

Junya Kondo, <jkondo@hatena.com>, Naoya Ito, <naoya@hatena.ne.jp>, Kentaro Kuribayashi, <kentarok@gmail.com>, Yuichi Tateno, <secondlife at hatena ne jp<gt>,

Kazuhiro Osawa <yappo <at> shibuya <döt> pl>

thanks to

naoya, kentaro, tokuhirom, kan, lopnor

REPOSITORY

svn co http://svn.coderepos.org/share/lang/perl/List-Rubyish/trunk List-Rubyish

List::Rubyish is Subversion repository is hosted at http://coderepos.org/share/. patches and collaborators are welcome.

LICENSE

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

DBIx::MoCo::List's COPYRIGHT

Copyright (C) Hatena Inc. All Rights Reserved.