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README

NAME
    autobox::Core - Provide core functions to autoboxed scalars, arrays and
    hashes.

SYNOPSIS
      use autobox::Core;

      "Hello, World\n"->uc->print;

      my @list = (1, 5, 9, 2, 0, 4, 2, 1);
      @list->sort->reverse->print;

      # works with references too!
      my $list = [1, 5, 9, 2, 0, 4, 2, 1];
      $list->sort->reverse->print;

      my %hash = (
          grass => 'green',
          apple => 'red',
          sky   => 'blue',
      );

      use feature qw(say);  # Use print and a newline in older versions of Perl

      [10, 20, 30, 40, 50]->pop->say;
      [10, 20, 30, 40, 50]->shift->say;

      my $lala = "Lalalalala\n"; 
      "chomp: "->concat($lala->chomp, " ", $lala)->say;

      my $hashref = { foo => 10, bar => 20, baz => 30, qux => 40 };

      print "hash keys: ", $hashref->keys->join(' '), "\n"; # or if you prefer...
      print "hash keys: ", join ' ', $hashref->keys(), "\n"; # or
      print "hash keys: "; $hashref->keys->say;

DESCRIPTION
    The autobox module promotes Perl's primitive types (literals (strings
    and numbers), scalars, arrays and hashes) into first-class objects.
    However, autobox does not provide any methods for these new classes.

    autobox::CORE provides a set of methods for these new classes. It
    includes almost everything in perlfunc, some things from Scalar::Util
    and List::Util, and some Perl 5 versions of methods taken from Perl 6.

    With autobox::Core one is able to change this:

            print join(" ", reverse(split(" ", $string)));

    to this:

            use autobox::Core;

            $string->split(" ")->reverse->print;

    Likewise you can change this:

            my $array_ref = [qw(fish dog cat elephant bird)];

            push @$array_ref, qw(snake lizard giraffe mouse);

    to this:

            use autobox::Core;
            my $array_ref = [qw(fish dog cat elephant bird)];

            $array_ref->push( qw(snake lizard giraffe mouse));

    autobox::Core makes it easier to avoid parentheses pile ups and messy
    dereferencing syntaxes.

    autobox::Core is mostly glue. It presents existing functions with a new
    interface, while adding few extra. Most of the methods read like `sub
    hex { CORE::hex($_[0]) }'. In addition to built-ins from perlfunc that
    operate on hashes, arrays, scalars, and code references, some Perl 6-ish
    things have been included, and some keywords like `foreach' are
    represented too.

  What's Implemented?
    *   All of the functions listed in perlfunc under the headings:

        *   "Functions for real @ARRAYs",

        *   "Functions for real %HASHes",

        *   "Functions for list data",

        *   "Functions for SCALARs or strings"

        plus a few taken from other sections and documented below.

    *   Some methods from Scalar::Util and List::Util.

    *   Some things expected in Perl 6, such as `last' (`last_idx'),
        `elems', and `curry'.

    *   `flatten' explicitly flattens an array.

    *   Functions such as `add' have been defined for numeric operations.

    String Methods
    String methods are of the form `my $return = $string->method(@args)'.
    Some will act on the `$string' and some will return a new string.

    Many string methods are simply wrappers around core functions, but there
    are additional operations and modifications to core behavior.

    Anything which takes a regular expression, such as split and m, usually
    take it in the form of a compiled regex (`qr//'). Any modifiers can be
    attached to the `qr' normally.

    These built in functions are implemented for scalars, they work just
    like normal: chomp, chop,chr crypt, index, lc lcfirst, length, ord,
    pack, reverse (always in scalar context), rindex, sprintf, substr, uc
    ucfirst, unpack, quotemeta, vec, undef, split, system, eval.

    In addition, so are each of the following:

    concat
       $string1->concat($string2);

    Concatenates `$string2' to `$string1'. This corresponds to the `.'
    operator used to join two strings. Returns the joined strings.

    strip
    Removes whitespace from the beginning and end of a string.

       " \t  \n  \t  foo  \t  \n  \t  "->strip;    # foo

    This is redundant and subtly different from `trim' which allows for the
    removal of specific characters from the beginning and end of a string.

    trim
    Removes whitespace from the beginning and end of a string. `trim' can
    also remove specific characters from the beginning and the end of
    string.

       '    hello'->trim;                   # 'hello'
       '*+* hello *+*'->trim("*+");         # ' hello ' 
       ' *+* hello *+*'->trim("*+");        # ' *+* hello'

    ltrim
    Just like trim but it only trims the left side (start) of the string.

       '    hello'->ltrim;                  # 'hello'
       '*+* hello *+*'->trim("*+");         # ' hello *+*'

    rtrim
    Just like trim but it only trims the right side (end) of the string.

       'hello   '->rtrim;                   # 'hello'
       '*+* hello *+*'->rtrim("*+");        # '*+* hello '

    split
        my @split_string = $string->split(qr/.../);

    A wrapper around split. It takes the regular expression as a compiled
    regex.

       print "10, 20, 30, 40"->split(qr{, ?})->elements, "\n";
       "hi there"->split(qr/ */);           # h i t h e r e

    The limit argument is not implemented.

    title_case
    `title_case' converts the first character of each word in the string to
    upper case.

       "this is a test"->title_case;        # This Is A Test

    center
        my $centered_string = $string->center($length);
        my $centered_string = $string->center($length, $character);

    Centers $string between $character. $centered_string will be of length
    $length, or the length of $string, whichever is greater.

    `$character' defaults to " ".

        say "Hello"->center(10);        # "   Hello  ";
        say "Hello"->center(10, '-');   # "---Hello--";

    `center()' will never truncate `$string'. If $length is less than
    `$string->length' it will just return `$string'.

        say "Hello"->center(4);        # "Hello";   

    backtick
        my $output = $string->backtick;

    Runs $string as a command just like ``$string`'.

    nm
        if( $foo->nm(qr/bar/) ) {
            say "$foo did not match 'bar'";
        }

    "Negative match". Corresponds to `!~'. Otherwise works in the same way
    as `m()'.

    m
        if( $foo->m(qr/bar/) ) {
            say "$foo matched 'bar'";
        }

        my $matches = $foo->m( qr/(\d*) (\w+)/ );
        say $matches->[0];
        say $matches->[1];

    Works the same as `m//', but the regex must be passed in as a `qr//'.

    `m' returns an array reference so that list functions such as `map' and
    `grep' may be called on the result. Use `elements' to turn this into a
    list of values.

      my ($street_number, $street_name, $apartment_number) =
          "1234 Robin Drive #101"->m( qr{(\d+) (.*)(?: #(\d+))?} )->elements;

      print "$street_number $street_name $apartment_number\n";

    s
      my $string = "the cat sat on the mat";
      $string->s( qr/cat/, "dog" );
      $string->say;                 # the dog sat on the mat
  
    Works the same as `s///'. Returns the number of substitutions performed,
    not the target string.

    undef
        $string->undef;

    Assigns `undef' to the `$string'.

    defined
        my $is_defined = $string->defined;

        if( not $string->defined ) {
            # give $string a value...
        }

    `defined' tests whether a value is defined (not `undef').

    repeat
        my $repeated_string = $string->repeat($n);

    Like the `x' operator, repeats a string `$n' times.

        print 1->repeat(5);     # 11111
        print "\n"->repeat(10); # ten newlines

    I/O Methods
    These are methods having to do with input and ouptut, not filehandles.

    print
        $string->print;

    Prints a string or a list of strings. Returns true if successful.

    say
    Like print, but implicitly appends a newline to the end.

         $string->say;

    Boolean Methods
    Methods related to boolean operations.

    and
    `and' corresponds to `&&'. Returns true if both operands are true.

            if( $a->and($b) ) {
                ...
            }

    not
    `not' corresponds to `!'. Returns true if the subject is false.

            if( $a->not ) {
                ...
            }

    or
    `or' corresponds to `||'. Returns true if at least one of the operands
    is true.

            if( $a->or($b) ) {
                ...
            }

    xor
    `xor' corresponds to `xor'. Returns true if only one of the operands is
    true.

            if( $a->xor($b) ) {
                ...
            }

    Number Related Methods
    Methods related to numbers.

    The basic built in functions which operate as normal : abs, atan2, cos,
    exp, int, log, oct, hex, sin, and sqrt.

    The following operators were also included:

    dec
        $number->dec();
        # $number is smaller by 1.

    `dec' corresponds to `++'. Decrements subject, will decrement character
    strings too: 'b' decrements to 'a'.

    inc
    `inc' corresponds to `++'. Increments subject, will increment character
    strings too. 'a' increments to 'b'.

    mod
    `mod' corresponds to `%'.

            $number->mod(5);

    pow
    `pow' returns $number raised to the power of the $exponent.

        my $result = $number->pow($expontent);
        print 2->pow(8);  # 256

    is_number
        $is_a_number = $thing->is_number;

    Returns true if $thing is a number as understood by Perl.

        12.34->is_number;           # true
        "12.34"->is_number;         # also true

    is_positive
        $is_positive = $thing->is_positive;

    Returns true if $thing is a positive number.

    `0' is not positive.

    is_negative
        $is_negative = $thing->is_negative;

    Returns true if $thing is a negative number.

    `0' is not negative.

    is_integer
        $is_an_integer = $thing->is_integer;

    Returns true if $thing is an integer.

        12->is_integer;             # true
        12.34->is_integer;          # false

    is_int
    A synonym for is_integer.

    is_decimal
        $is_a_decimal_number = $thing->is_decimal;

    Returns true if $thing is a decimal number.

        12->is_decimal;             # false
        12.34->is_decimal;          # true
        ".34"->is_decimal;          # true

    Reference Related Methods
    The following core functions are implemented.

    tie, tied, ref, vec.

    `tie', `tied', and `undef' don't work on code references.

    Array Methods
    Array methods work on both arrays and array references:

      my $arr = [ 1 .. 10 ];
      $arr->undef;

    Or:

      my @arr = [ 1 .. 10 ];
      @arr->undef;

    List context forces methods to return a list:

      my @arr = ( 1 .. 10 );
      print join ' -- ', @arr->grep(sub { $_ > 3 }), "\n";

    Likewise, scalar context forces methods to return an array reference.

    As scalar context forces methods to return a reference, methods may be
    chained

      my @arr = ( 1 .. 10 );
      @arr->grep(sub { $_ > 3 })->min->say;  # "1\n";

    These built-in functions are defined as methods:

    pop, push, shift, unshift, delete, undef, exists, bless, tie, tied, ref,
    grep, map, join, reverse, and sort, each,

    vdelete
    Deletes a specified value from the array.

      $a = 1->to(10);
      $a->vdelete(3);         # deletes 3
      $a->vdelete(2)->say;    # "1 4 5 6 7 8 9 10\n"

    uniq
    Removes all duplicate elements from an array and returns the new array
    with no duplicates.

       my @array = qw( 1 1 2 3 3 6 6 );
       @return = @array->uniq;    # @return : 1 2 3 6

    first
    Returns the first element of an array for which a callback returns true:

      $arr->first(sub { qr/5/ });

    max
    Returns the largest numerical value in the array.

       $a = 1->to(10);
       $a->max;           # 10

    min
    Returns the smallest numerical value in the array.

       $a = 1->to(10);
       $a->min;           # 1

    mean
    Returns the mean of elements of an array.

       $a = 1->to(10);
       $a->mean;          # 55/10

    var
    Returns the variance of the elements of an array.

       $a = 1->to(10);
       $a->var;           # 33/4

    svar
    Returns the standard variance.

      $a = 1->to(10);
      $a->svar;                     # 55/6

    at
    Returns the element at a specified index. This function does not modify
    the original array.

       $a = 1->to(10);
       $a->at(2);                   # 3

    size
    See length().

    elems
    See length().

    length
    `size', `elems' and `length' all return the number of elements in an
    array.

       my @array = qw(foo bar baz);
       @array->size;   # 3

    elements
    See `flatten'.

    flatten
        my @copy_of_array = $array->flatten;

    Returns the elements of an array ref as an array. This is the same as
    `@{$array}'.

    Arrays can be iterated on using `for' and `foreach'. Both take a code
    reference as the body of the for statement.

    foreach
        @array->foreach(\&code);

    Calls `&code' on each element of the @array in order. &code gets the
    element as its argument.

        @array->foreach(sub { print $_[0] });  # print each element of the array

    for
        @array->for(\&code);

    Like foreach, but `&code' is called with the index, the value and the
    array itself.

        my $arr = [ 1 .. 10 ];
        $arr->for(sub {
            my($idx, $value) = @_;
            print "Value #$idx is $value\n";
        });

    sum
        my $sum = @array->sum;

    Adds together all the elements of the array.

    count
    Returns the number of elements in array that are `eq' to a specified
    value:

      my @array = qw/one two two three three three/;
      my $num = @array->count('three');  # returns 3

    to, upto, downto
    `to', `upto', and `downto' create array references:

       1->to(5);      # creates [1, 2, 3, 4, 5]
       1->upto(5);    # creates [1, 2, 3, 4, 5]
       5->downto(5);  # creates [5, 4, 3, 2, 1]

    Those wrap the `..' operator.

    Note while working with negative numbers you need to use () so as to
    avoid the wrong evaluation.

      my $range = 10->to(1);        # this works
      my $range = -10->to(10);      # wrong, interpreted as -( 10->to(10) )
      my $range = (-10)->to(10);    # this works

    head
    Returns the first element from `@list'. This differs from shift in that
    it does not change the array.

        my $first = @list->head;

    tail
    Returns all but the first element from `@list'.

        my @list = qw(foo bar baz quux);
        my @rest = @list->tail;  # [ 'bar', 'baz', 'quux' ]

    Optionally, you can pass a number as argument to ask for the last `$n'
    elements:

        @rest = @list->tail(2); # [ 'baz', 'quux' ]

    slice
    Returns a list containing the elements from `@list' at the indices
    `@indices'. In scalar context, returns an array reference.

        # Return $list[1], $list[2], $list[4] and $list[8].
        my @sublist = @list->slice(1,2,4,8);

    range
    `range' returns a list containing the elements from `@list' with indices
    ranging from `$lower_idx' to `$upper_idx'. It returns an array reference
    in scalar context.

        my @sublist = @list->range( $lower_idx, $upper_idx );

    last_index
        my $index = @array->last_index(qr/.../);

    Returns the highest index whose element matches the given regular
    expression.

        my $index = @array->last_index(\&filter);

    Returns the highest index for an element on which the filter returns
    true. The &filter is passed in each value of the @array.

        my @things = qw(pear poll potato tomato);
        my $last_p = @things->last_index(qr/^p/); # 2

    Called with no arguments, it corresponds to `$#array' giving the highest
    index of the array.

        my $index = @array->last_index;

    first_index
    Works just like last_index but it will return the index of the *first*
    matching element.

        my $first_index = @array->first_index;    # 0

        my @things = qw(pear poll potato tomato);
        my $last_p = @things->first_index(qr/^t/); # 3

    at
        my $value = $array->at($index);

    Equivalent to `$array->[$index]'.

    Hash Methods
    Hash methods work on both hashes and hash references.

    The built in functions work as normal:

    delete, exists, keys, values, bless, tie, tied, ref, undef,

    at
    See `at'.

    get
        my @values = %hash->get(@keys);

    Returns the @values of @keys.

    put
        %hash->put(%other_hash);

    Overlays %other_hash on top of %hash.

       my $h = {a => 1, b => 2};
       $h->put(b => 99, c => 3);    # (a => 1, b => 99, c => 3)

    set
    Synonym for put.

    each
    Like `foreach' but for hash references. For each key in the hash, the
    code reference is invoked with the key and the corresponding value as
    arguments:

      my $hashref = { foo => 10, bar => 20, baz => 30, quux => 40 };
      $hashref->each(sub { print $_[0], ' is ', $_[1], "\n" });

    Or:

      my %hash = ( foo => 10, bar => 20, baz => 30, quux => 40 );
      %hash->each(sub { print $_[0], ' is ', $_[1], "\n" });

    Unlike regular `each', this each will always iterate through the entire
    hash.

    Hash keys appear in random order that varies from run to run (this is
    intentional, to avoid calculated attacks designed to trigger algorithmic
    worst case scenario in `perl''s hash tables).

    You can get a sorted `foreach' by combining `keys', `sort', and
    `foreach':

       %hash->keys->sort->foreach(sub {
          print $_[0], ' is ', $hash{$_[0]}, "\n";
       });

    lock_keys
        %hash->lock_keys;

    Works as Hash::Util. No more keys may be added to the hash.

    slice
    Takes a list of hash keys and returns the corresponding values e.g.

      my %hash = (
          one   => 'two',
          three => 'four',
          five  => 'six'
      );

      print %hash->slice(qw(one five))->join(' and '); # prints "two and six"

    flip
    Exchanges values for keys in a hash:

        my %things = ( foo => 1, bar => 2, baz => 5 );
        my %flipped = %things->flip; # { 1 => foo, 2 => bar, 5 => baz }

    If there is more than one occurence of a certain value, any one of the
    keys may end up as the value. This is because of the random ordering of
    hash keys.

        # Could be { 1 => foo }, { 1 => bar }, or { 1 => baz }
        { foo => 1, bar => 1, baz => 1 }->flip;

    Because references cannot usefully be keys, it will not work where the
    values are references.

        { foo => [ 'bar', 'baz' ] }->flip; # dies

    flatten
        my %hash = $hash_ref->flatten;

    Dereferences a hash reference.

    Code Methods
    Methods which work on code references.

    These are simple wrappers around the Perl core functions. bless, ref,

    Due to Perl's precedence rules, some autoboxed literals may need to be
    parenthesized. For instance, this works:

      my $curried = sub { ... }->curry();

    This does not:

      my $curried = \&foo->curry();

    The solution is to wrap the reference in parentheses:

      my $curried = (\&foo)->curry();

    curry
        my $curried_code = $code->curry(5);

    Currying takes a code reference and provides the same code, but with the
    first argument filled in.

        my $greet_world = sub {
            my($greeting, $place) = @_;
            return "$greeting, $place!";
        };
        print $greet_world->("Hello", "world");  # "Hello, world!"

        my $howdy_world = $greet_world->curry("Howdy");
        print $howdy_world->("Texas");           # "Howdy, Texas!"

  What's Missing?
    *   File and socket operations are already implemented in an
        object-oriented fashion care of IO::Handle, IO::Socket::INET, and
        IO::Any.

    *   Functions listed in the perlfunc headings

        *   "System V interprocess communication functions",

        *   "Fetching user and group info",

        *   "Fetching network info",

        *   "Keywords related to perl modules",

        *   "Functions for processes and process groups",

        *   "Keywords related to scoping",

        *   "Time-related functions",

        *   "Keywords related to the control flow of your perl program",

        *   "Functions for filehandles, files, or directories",

        *   "Input and output functions".

    *   (Most) binary operators

    These things are likely implemented in an object oriented fashion by
    other CPAN modules, are keywords and not functions, take no arguments,
    or don't make sense as part of the string, number, array, hash, or code
    API.

  Autoboxing
    *This section quotes four pages from the manuscript of Perl 6 Now: The
    Core Ideas Illustrated with Perl 5 by Scott Walters. The text appears in
    the book starting at page 248. This copy lacks the benefit of copyedit -
    the finished product is of higher quality.*

    A *box* is an object that contains a primitive variable. Boxes are used
    to endow primitive types with the capabilities of objects which
    essential in strongly typed languages but never strictly required in
    Perl. Programmers might write something like `my $number = Int->new(5)'.
    This is manual boxing. To *autobox* is to convert a simple type into an
    object type automatically, or only conceptually. This is done by the
    language.

    *autobox*ing makes a language look to programmers as if everything is an
    object while the interpreter is free to implement data storage however
    it pleases. Autoboxing is really making simple types such as numbers,
    strings, and arrays appear to be objects.

    `int', `num', `bit', `str', and other types with lower case names, are
    primitives. They're fast to operate on, and require no more memory to
    store than the data held strictly requires. `Int', `Num', `Bit', `Str',
    and other types with an initial capital letter, are objects. These may
    be subclassed (inherited from) and accept traits, among other things.
    These objects are provided by the system for the sole purpose of
    representing primitive types as objects, though this has many ancillary
    benefits such as making `is' and `has' work. Perl provides `Int' to
    encapsulate an `int', `Num' to encapsulate a `num', `Bit' to encapsulate
    a `bit', and so on. As Perl's implementations of hashes and dynamically
    expandable arrays store any type, not just objects, Perl programmers
    almost never are required to box primitive types in objects. Perl's
    power makes this feature less essential than it is in other languages.

    *autobox*ing makes primitive objects and they're boxed versions
    equivalent. An `int' may be used as an `Int' with no constructor call,
    no passing, nothing. This applies to constants too, not just variables.
    This is a more Perl 6 way of doing things.

      # Perl 6 - autoboxing associates classes with primitives types:
 
      print 4.sqrt, "\n";

      print [ 1 .. 20 ].elems, "\n";

    The language is free to implement data storage however it wishes but the
    programmer sees the variables as objects.

    Expressions using autoboxing read somewhat like Latin suffixes. In the
    autoboxing mind-set, you might not say that something is "made more
    mnemonic", but has been "mnemonicified".

    Autoboxing may be mixed with normal function calls. In the case where
    the methods are available as functions and the functions are available
    as methods, it is only a matter of personal taste how the expression
    should be written:

      # Calling methods on numbers and strings, these three lines are equivalent
      # Perl 6

      print sqrt 4;
      print 4.sqrt;
      4.sqrt.print;

    The first of these three equivalents assumes that a global `sqrt()'
    function exists. This first example would fail to operate if this global
    function were removed and only a method in the `Num' package was left.

    Perl 5 had the beginnings of autoboxing with filehandles:

      use IO::Handle;
      open my $file, '<', 'file.txt' or die $!;
      $file->read(my $data, -s $file);

    Here, `read' is a method on a filehandle we opened but *never blessed*.
    This lets us say things like `$file->print(...)' rather than the often
    ambagious `print $file ...'.

    To many people, much of the time, it makes more conceptual sense as
    well.

    Reasons to Box Primitive Types
    What good is all of this?

    *   Makes conceptual sense to programmers used to object interfaces as
        *the* way to perform options.

    *   Alternative idiom. Doesn't require the programmer to write or read
        expressions with complex precedence rules or strange operators.

    *   Many times that parenthesis would otherwise have to span a large
        expression, the expression may be rewritten such that the
        parenthesis span only a few primitive types.

    *   Code may often be written with fewer temporary variables.

    *   Autoboxing provides the benefits of boxed types without the memory
        bloat of actually using objects to represent primitives. Autoboxing
        "fakes it".

    *   Strings, numbers, arrays, hashes, and so on, each have their own
        API. Documentation for an `exists' method for arrays doesn't have to
        explain how hashes are handled and vice versa.

    *   Perl tries to accommodate the notion that the "subject" of a
        statement should be the first thing on the line, and autoboxing
        furthers this agenda.

    Perl is an idiomatic language and this is an important idiom.

    Subject First: An Aside
    Perl's design philosophy promotes the idea that the language should be
    flexible enough to allow programmers to place the of a statement first.
    For example, `die $! unless read $file, 60' looks like the primary
    purpose of the statement is to `die'.

    While that might be the programmers primary goal, when it isn't, the
    programmer can communicate his real primary intention to programmers by
    reversing the order of clauses while keeping the exact same logic: `read
    $file, 60 or die $!'.

    Autoboxing is another way of putting the subject first.

    Nouns make good subjects, and in programming, variables, constants, and
    object names are the nouns. Function and method names are verbs.
    `$noun->verb()' focuses the readers attention on the thing being acted
    on rather than the action being performed. Compare to `$verb($noun)'.

    Autoboxing and Method Results
    Let's look at some examples of ways an expression could be written.

      # Various ways to do the same thing:

      print(reverse(sort(keys(%hash))));          # Perl 5 - pathological parenthetic
      print reverse sort keys %hash;              # Perl 5 - no unneeded parenthesis

      print(reverse(sort(%hash,keys))));          # Perl 6 - pathological
      print reverse sort %hash.keys;              # Perl 6 - no unneeded parenthesis

      %hash.keys ==> sort ==> reverse ==> print;  # Perl 6 - pipeline operator

      %hash.keys.sort.reverse.print;              # Perl 6 - autobox

      %hash->keys->sort->reverse->print;          # Perl 5 - autobox

    This section deals with the last two of these equivalents. These are
    method calls

      use autobox::Core;
      use Perl6::Contexts;

      my %hash = (foo => 'bar', baz => 'quux');

      %hash->keys->sort->reverse->print;          # Perl 5 - autobox

      # prints "foo baz"

    Each method call returns an array reference, in this example. Another
    method call is immediately performed on this value. This feeding of the
    next method call with the result of the previous call is the common mode
    of use of autoboxing. Providing no other arguments to the method calls,
    however, is not common.

    `Perl6::Contexts' recognizes object context as provided by `->' and
    coerces `%hash' and `@array' into references, suitable for use with
    `autobox'. (Note that `autobox' also does this automatically as of
    version 2.40.)

    `autobox' associates primitive types, such as references of various
    sorts, with classes. `autobox::Core' throws into those classes methods
    wrapping Perl's built-in functions. In the interest of full disclosure,
    `Perl6::Contexts' and `autobox::Core' are my creations.

    Autobox to Simplify Expressions
    One of my pet peeves in programming is parenthesis that span large
    expression. It seems like about the time I'm getting ready to close the
    parenthesis I opened on the other side of the line, I realize that I've
    forgotten something, and I have to arrow back over or grab the mouse.

    When the expression is too long to fit on a single line, it gets broken
    up, then I must decide how to indent it if it grows to 3 or more lines.

      # Perl 5 - a somewhat complex expression

      print join("\n", map { CGI::param($_) } @cgi_vars), "\n";
      # Perl 5 - again, using autobox:

      @cgi_vars->map(sub { CGI::param($_[0]) })->join("\n")->concat("\n")->print;

    The autoboxed version isn't shorter, but it reads from left to right,
    and the parenthesis from the `join()' don't span nearly as many
    characters. The complex expression serving as the value being `join()'ed
    in the non-autoboxed version becomes, in the autoboxed version, a value
    to call the `join()' method on.

    This `print' statement takes a list of CGI parameter names, reads the
    values for each parameter, joins them together with newlines, and prints
    them with a newline after the last one.

    Pretending that this expression were much larger and it had to be broken
    to span several lines, or pretending that comments are to be placed
    after each part of the expression, you might reformat it as such:

      @cgi_vars->map(sub { CGI::param($_[0]) })  # turn CGI arg names into values
               ->join("\n")                      # join with newlines
               ->concat("\n")                    # give it a trailing newline
               ->print;                          # print them all out

    This could also have been written:

      sub { CGI::param($_[0]) }->map(@cgi_vars)  # turn CGI arg names into values
               ->join("\n")                      # join with newlines
               ->concat("\n")                    # give it a trailing newline
               ->print;                          # print them all out

    `map()' is .

    The `map()' method defined in the `autobox::Core::CODE' package takes
    for its arguments the things to map. The `map()' method defined in the
    `autobox::Core::ARRAY' package takes for its argument a code reference
    to apply to each element of the array.

    *Here ends the text quoted from the Perl 6 Now manuscript.*

BUGS
    Yes. Report them to the author, scott@slowass.net, or post them to
    GitHub's bug tracker at https://github.com/scrottie/autobox-Core/issues.

    The API is not yet stable -- Perl 6-ish things and local extensions are
    still being renamed.

HISTORY
    See the Changes file.

COPYRIGHT AND LICENSE
    Copyright (C) 2009, 2010, 2011 by Scott Walters and various contributors
    listed (and unlisted) below.

    This library is free software; you can redistribute it and/or modify it
    under the same terms as Perl itself, either Perl version 5.8.9 or, at
    your option, any later version of Perl 5 you may have available.

    This library is distributed in the hope that it will be useful, but
    without any warranty; without even the implied warranty of
    merchantability or fitness for a particular purpose.

SEE ALSO
    autobox
    Moose::Autobox
    Perl6::Contexts
    http://github.com/gitpan/autobox-Core
    IO::Any
    Perl 6: http://dev.perl.org/perl6/apocalypse/.

AUTHORS
    Scott Walters, scott@slowass.net.

    Michael Schwern and the perl5i contributors for tests, code, and
    feedback.

    JJ contributed a `strip' method for scalars - thanks JJ!

    Ricardo SIGNES contributed patches.

    Thanks to Matt Spear, who contributed tests and definitions for numeric
    operations.

    Mitchell N Charity reported a bug and sent a fix.

    Thanks to chocolateboy for autobox and for the encouragement.

    Thanks to Bruno Vecchi for bug fixes and many, many new tests going into
    version 0.8.

    Thanks to http://github.com/daxim daxim/Lars DIECKOW pushing in fixes
    and patches from the RT queue along with fixes to build and additional
    doc examples.

    Jacinta Richardson improved documentation.

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