Encode::Encoder(3p) Perl Programmers Reference Guide Encode::Encoder(3p) #

Encode::Encoder(3p) Perl Programmers Reference Guide Encode::Encoder(3p)

NNAAMMEE #

 Encode::Encoder -- Object Oriented Encoder

SSYYNNOOPPSSIISS #

   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)

AABBSSTTRRAACCTT #

 EEnnccooddee::::EEnnccooddeerr allows you to use Encode in an object-oriented style.
 This is not only more intuitive than a 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 the lazier and more convoluted

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

DDeessccrriippttiioonn Here is how to use this module.

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

 •   When there is no method, it takes the method name as the name of the
     encoding and encodes the instance _d_a_t_a with _e_n_c_o_d_i_n_g.  If successful,
     the instance _e_n_c_o_d_i_n_g 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.

PPrreeddeeffiinneedd MMeetthhooddss This module predefines the methods below:

 $e = Encode::Encoder->new([$data, $encoding]);
     returns an encoder object.  Its data is initialized with $data if
     present, and its encoding is set to $encoding if present.

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

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

 $e->data([$data])
     When $data is present, sets the instance data to $data and returns
     the object itself.  Otherwise, the current instance data is returned.

 $e->encoding([$encoding])
     When $encoding is present, sets the 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 the instance encoding if
     omitted.  If the conversion is successful, the instance encoding will
     be set to "".

     The name _b_y_t_e_s 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.

EExxaammppllee:: bbaassee6644 ttrraannssccooddeerr This module is designed to work with Encode::Encoding. To make the Base64 transcoder example above really work, you could write a module like this:

   package Encode::Base64;
   use parent '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 would be something 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;

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

 Stringify dumps the data inside the object.

 Numify returns the number of bytes in the instance data.

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

SSEEEE AALLSSOO #

 Encode, Encode::Encoding

perl v5.36.3 2014-11-17 Encode::Encoder(3p)