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NAME

Encode::Encoder -- Object Oriented Encoder

SYNOPSIS

  use Encode::Encoder;
  # Encode::encode("ISO-8859-1", $data); 
  Encode::Encoder->new($data)->iso_8859_1; # OOP way
  # shortcut
  use Encode::Encoder qw(encoder);
  encoder($data)->iso_8859_1;
  # you can stack them!
  encoder($data)->iso_8859_1->base64;  # provided base64() is defined
  # you can use it as a decoder as well
  encoder($base64)->bytes('base64')->latin1;
  # stringified
  print encoder($data)->utf8->latin1;  # prints the string in latin1
  # numified
  encoder("\x{abcd}\x{ef}g")->utf8 == 6; # true. bytes::length($data)

ABSTRACT

Encode::Encoder allows you to use Encode via OOP style. This is not only more intuitive than functional approach, but also handier when you want to stack encodings. Suppose you want your UTF-8 string converted to Latin1 then Base64, you can simply say

  my $base64 = encoder($utf8)->latin1->base64;

instead of

  my $latin1 = encode("latin1", $utf8);
  my $base64 = encode_base64($utf8);

or lazier and convolted

  my $base64 = encode_base64(encode("latin1", $utf8));

Description

Here is how to use this module.

  • There are at least two instance variable stored in hash reference, {data} and {encoding}.

  • When there is no method, it takes the method name as the name of encoding and encode instance data with encoding. If successful, instance encoding is set accordingly.

  • You can retrieve the result via ->data but usually you don't have to because the stringify operator ("") is overridden to do exactly that.

Predefined Methods

This module predefines the methods below;

$e = Encode::Encoder->new([$data, $encoding]);

returns an encoder object. Its data is initialized with $data if there, and its encoding is set to $encoding if there.

When $encoding is omitted, it defaults to utf8 if $data is already in utf8 or "" (empty string) otherwise.

encoder()

is an alias of Encode::Encoder->new(). This one is exported on demand.

$e->data([$data])

when $data is present, sets instance data to $data and returns the object itself. otherwise the current instance data is returned.

$e->encoding([$encoding])

when $encoding is present, sets instance encoding to $encoding and returns the object itself. otherwise the current instance encoding is returned.

$e->bytes([$encoding])

decodes instance data from $encoding, or instance encoding if omitted. when the conversion is successful, the enstance encoding will be set to "" .

The name bytes was deliberately picked to avoid namespace tainting -- this module may be used as a base class so method names that appear in Encode::Encoding are avoided.

Example: base64 transcoder

This module is desined to work with Encode::Encoding. To make the Base64 transcorder example above really work, you should write a module like this.

  package Encode::Base64;
  use base 'Encode::Encoding';
  __PACKAGE__->Define('base64');
  use MIME::Base64;
  sub encode{ 
      my ($obj, $data) = @_; 
      return encode_base64($data);
  }
  sub decode{
      my ($obj, $data) = @_; 
      return decode_base64($data);
  }
  1;
  __END__

And your caller module should be like this;

  use Encode::Encoder;
  use Encode::Base64;

  # now you can really do the following

  encoder($data)->iso_8859_1->base64;
  encoder($base64)->bytes('base64')->latin1;

operator overloading

This module overloads two operators, stringify ("") and numify (0+).

Stringify dumps the data therein.

Numify returns the number of bytes therein.

They come in handy when you want to print or find the size of data.

SEE ALSO

Encode Encode::Encoding