3 our $VERSION = do { my @r = (q$Revision: 1.52 $ =~ /\d+/g); sprintf "%d."."%02d" x $#r, @r };
6 XSLoader::load 'Encode';
9 our @ISA = qw(Exporter);
11 # Public, encouraged API is exported by default
14 decode decode_utf8 encode encode_utf8
15 encodings find_encoding
18 our @FB_FLAGS = qw(DIE_ON_ERR WARN_ON_ERR RETURN_ON_ERR LEAVE_SRC PERLQQ);
19 our @FB_CONSTS = qw(FB_DEFAULT FB_QUIET FB_WARN FB_PERLQQ FB_CROAK);
24 _utf8_off _utf8_on define_encoding from_to is_16bit is_8bit
25 is_utf8 perlio_ok resolve_alias utf8_downgrade utf8_upgrade
27 @FB_FLAGS, @FB_CONSTS,
32 all => [ @EXPORT, @EXPORT_OK ],
33 fallbacks => [ @FB_CONSTS ],
34 fallback_all => [ @FB_CONSTS, @FB_FLAGS ],
37 # Documentation moved after __END__ for speed - NI-S
41 our $ON_EBCDIC = (ord("A") == 193);
45 # Make a %Encoding package variable to allow a certain amount of cheating
48 require Encode::Config;
49 eval { require Encode::ConfigLocal };
54 my @modules = (@_ and $_[0] eq ":all") ? values %ExtModule : @_;
55 for my $mod (@modules){
56 $mod =~ s,::,/,g or $mod = "Encode/$mod";
58 $DEBUG and warn "about to require $mod;";
59 eval { require $mod; };
61 my %modules = map {$_ => 1} @modules;
63 sort { lc $a cmp lc $b }
64 grep {!/^(?:Internal|Unicode)$/o} keys %Encoding;
68 exists $INC{"PerlIO/encoding.pm"} or return 0;
69 my $stash = ref($_[0]);
70 $stash ||= ref(find_encoding($_[0]));
71 return ($stash eq "Encode::XS" || $stash eq "Encode::Unicode");
78 $Encoding{$name} = $obj;
80 define_alias($lc => $obj) unless $lc eq $name;
84 define_alias($alias,$obj);
91 my ($class,$name,$skip_external) = @_;
93 if (ref($name) && $name->can('new_sequence'))
98 if (exists $Encoding{$name})
100 return $Encoding{$name};
102 if (exists $Encoding{$lc})
104 return $Encoding{$lc};
107 my $oc = $class->find_alias($name);
108 return $oc if defined $oc;
110 $oc = $class->find_alias($lc) if $lc ne $name;
111 return $oc if defined $oc;
113 unless ($skip_external)
115 if (my $mod = $ExtModule{$name} || $ExtModule{$lc}){
116 $mod =~ s,::,/,g ; $mod .= '.pm';
117 eval{ require $mod; };
118 return $Encoding{$name} if exists $Encoding{$name};
126 my ($name,$skip_external) = @_;
127 return __PACKAGE__->getEncoding($name,$skip_external);
131 my $obj = find_encoding(shift);
132 defined $obj and return $obj->name;
138 my ($name,$string,$check) = @_;
140 my $enc = find_encoding($name);
141 croak("Unknown encoding '$name'") unless defined $enc;
142 my $octets = $enc->encode($string,$check);
143 return undef if ($check && length($string));
149 my ($name,$octets,$check) = @_;
151 my $enc = find_encoding($name);
152 croak("Unknown encoding '$name'") unless defined $enc;
153 my $string = $enc->decode($octets,$check);
154 $_[1] = $octets if $check;
160 my ($string,$from,$to,$check) = @_;
162 my $f = find_encoding($from);
163 croak("Unknown encoding '$from'") unless defined $f;
164 my $t = find_encoding($to);
165 croak("Unknown encoding '$to'") unless defined $t;
166 my $uni = $f->decode($string,$check);
167 return undef if ($check && length($string));
168 $string = $t->encode($uni,$check);
169 return undef if ($check && length($uni));
170 return defined($_[0] = $string) ? length($string) : undef ;
183 return undef unless utf8::decode($str);
187 predefine_encodings();
190 # This is to restore %Encoding if really needed;
192 sub predefine_encodings{
194 # was in Encode::UTF_EBCDIC
195 package Encode::UTF_EBCDIC;
196 *name = sub{ shift->{'Name'} };
197 *new_sequence = sub{ return $_[0] };
199 my ($obj,$str,$chk) = @_;
201 for (my $i = 0; $i < length($str); $i++) {
203 chr(utf8::unicode_to_native(ord(substr($str,$i,1))));
209 my ($obj,$str,$chk) = @_;
211 for (my $i = 0; $i < length($str); $i++) {
213 chr(utf8::native_to_unicode(ord(substr($str,$i,1))));
218 $Encode::Encoding{Unicode} =
219 bless {Name => "UTF_EBCDIC"} => "Encode::UTF_EBCDIC";
221 # was in Encode::UTF_EBCDIC
222 package Encode::Internal;
223 *name = sub{ shift->{'Name'} };
224 *new_sequence = sub{ return $_[0] };
226 my ($obj,$str,$chk) = @_;
232 $Encode::Encoding{Unicode} =
233 bless {Name => "Internal"} => "Encode::Internal";
237 # was in Encode::utf8
238 package Encode::utf8;
239 *name = sub{ shift->{'Name'} };
240 *new_sequence = sub{ return $_[0] };
242 my ($obj,$octets,$chk) = @_;
243 my $str = Encode::decode_utf8($octets);
251 my ($obj,$string,$chk) = @_;
252 my $octets = Encode::encode_utf8($string);
256 $Encode::Encoding{utf8} =
257 bless {Name => "utf8"} => "Encode::utf8";
261 require Encode::Encoding;
264 require PerlIO::encoding;
265 unless (PerlIO::encoding->VERSION >= 0.02){
266 delete $INC{"PerlIO/encoding.pm"};
270 @Encode::XS::ISA = qw(Encode::Encoding);
278 Encode - character encodings
285 =head2 Table of Contents
287 Encode consists of a collection of modules which details are too big
288 to fit in one document. This POD itself explains the top-level APIs
289 and general topics at a glance. For other topics and more details,
293 --------------------------------------------------------
294 Encode::Alias Alias definitions to encodings
295 Encode::Encoding Encode Implementation Base Class
296 Encode::Supported List of Supported Encodings
297 Encode::CN Simplified Chinese Encodings
298 Encode::JP Japanese Encodings
299 Encode::KR Korean Encodings
300 Encode::TW Traditional Chinese Encodings
301 --------------------------------------------------------
305 The C<Encode> module provides the interfaces between Perl's strings
306 and the rest of the system. Perl strings are sequences of
309 The repertoire of characters that Perl can represent is at least that
310 defined by the Unicode Consortium. On most platforms the ordinal
311 values of the characters (as returned by C<ord(ch)>) is the "Unicode
312 codepoint" for the character (the exceptions are those platforms where
313 the legacy encoding is some variant of EBCDIC rather than a super-set
314 of ASCII - see L<perlebcdic>).
316 Traditionally computer data has been moved around in 8-bit chunks
317 often called "bytes". These chunks are also known as "octets" in
318 networking standards. Perl is widely used to manipulate data of many
319 types - not only strings of characters representing human or computer
320 languages but also "binary" data being the machines representation of
321 numbers, pixels in an image - or just about anything.
323 When Perl is processing "binary data" the programmer wants Perl to
324 process "sequences of bytes". This is not a problem for Perl - as a
325 byte has 256 possible values it easily fits in Perl's much larger
334 I<character>: a character in the range 0..(2**32-1) (or more).
335 (What Perl's strings are made of.)
339 I<byte>: a character in the range 0..255
340 (A special case of a Perl character.)
344 I<octet>: 8 bits of data, with ordinal values 0..255
345 (Term for bytes passed to or from a non-Perl context, e.g. disk file.)
349 The marker [INTERNAL] marks Internal Implementation Details, in
350 general meant only for those who think they know what they are doing,
351 and such details may change in future releases.
353 =head1 PERL ENCODING API
357 =item $octets = encode(ENCODING, $string[, CHECK])
359 Encodes string from Perl's internal form into I<ENCODING> and returns
360 a sequence of octets. ENCODING can be either a canonical name or
361 alias. For encoding names and aliases, see L</"Defining Aliases">.
362 For CHECK see L</"Handling Malformed Data">.
364 For example to convert (internally UTF-8 encoded) Unicode string to
365 iso-8859-1 (also known as Latin1),
367 $octets = encode("iso-8859-1", $unicode);
369 =item $string = decode(ENCODING, $octets[, CHECK])
371 Decode sequence of octets assumed to be in I<ENCODING> into Perl's
372 internal form and returns the resulting string. as in encode(),
373 ENCODING can be either a canonical name or alias. For encoding names
374 and aliases, see L</"Defining Aliases">. For CHECK see
375 L</"Handling Malformed Data">.
377 For example to convert ISO-8859-1 data to UTF-8:
379 $utf8 = decode("iso-8859-1", $latin1);
381 =item [$length =] from_to($string, FROM_ENCODING, TO_ENCODING [,CHECK])
383 Convert B<in-place> the data between two encodings.
384 For example to convert ISO-8859-1 data to UTF-8:
386 from_to($data, "iso-8859-1", "utf-8");
388 and to convert it back:
390 from_to($data, "utf-8", "iso-8859-1");
392 Note that because the conversion happens in place, the data to be
393 converted cannot be a string constant, it must be a scalar variable.
395 from_to() return the length of the converted string on success, undef
402 The Unicode consortium defines the UTF-8 standard as a way of encoding
403 the entire Unicode repertoire as sequences of octets. This encoding is
404 expected to become very widespread. Perl can use this form internally
405 to represent strings, so conversions to and from this form are
406 particularly efficient (as octets in memory do not have to change,
407 just the meta-data that tells Perl how to treat them).
411 =item $octets = encode_utf8($string);
413 The characters that comprise string are encoded in Perl's superset of UTF-8
414 and the resulting octets returned as a sequence of bytes. All possible
415 characters have a UTF-8 representation so this function cannot fail.
417 =item $string = decode_utf8($octets [, CHECK]);
419 The sequence of octets represented by $octets is decoded from UTF-8
420 into a sequence of logical characters. Not all sequences of octets
421 form valid UTF-8 encodings, so it is possible for this call to fail.
422 For CHECK see L</"Handling Malformed Data">.
426 =head2 Listing available encodings
429 @list = Encode->encodings();
431 Returns a list of the canonical names of the available encodings that
432 are loaded. To get a list of all available encodings including the
433 ones that are not loaded yet, say
435 @all_encodings = Encode->encodings(":all");
437 Or you can give the name of specific module.
439 @with_jp = Encode->encodings("Encode::JP");
441 When "::" is not in the name, "Encode::" is assumed.
443 @ebcdic = Encode->encodings("EBCDIC");
445 To find which encodings are supported by this package in details,
446 see L<Encode::Supported>.
448 =head2 Defining Aliases
450 To add new alias to a given encoding, Use;
454 define_alias(newName => ENCODING);
456 After that, newName can be used as an alias for ENCODING.
457 ENCODING may be either the name of an encoding or an
460 But before you do so, make sure the alias is nonexistent with
461 C<resolve_alias()>, which returns the canonical name thereof.
464 Encode::resolve_alias("latin1") eq "iso-8859-1" # true
465 Encode::resolve_alias("iso-8859-12") # false; nonexistent
466 Encode::resolve_alias($name) eq $name # true if $name is canonical
468 This resolve_alias() does not need C<use Encode::Alias> and is
469 exported via C<use encode qw(resolve_alias)>.
471 See L<Encode::Alias> on details.
473 =head1 Encoding via PerlIO
475 If your perl supports I<PerlIO>, you can use PerlIO layer to directly
476 decode and encode via filehandle. The following two examples are
477 totally identical by functionality.
480 open my $in, "<:encoding(shiftjis)", $infile or die;
481 open my $out, ">:encoding(euc-jp)", $outfile or die;
485 open my $in, $infile or die;
486 open my $out, $outfile or die;
488 from_to($_, "shiftjis", "euc", 1);
491 Unfortunately, not all encodings are PerlIO-savvy. You can check if
492 your encoding is supported by PerlIO by C<perlio_ok> method.
494 Encode::perlio_ok("iso-20220jp"); # false
495 find_encoding("iso-2022-jp")->perlio_ok; # false
496 use Encode qw(perlio_ok); # exported upon request
497 perlio_ok("euc-jp") # true if PerlIO is enabled
499 For gory details, see L<Encode::PerlIO>;
501 =head1 Handling Malformed Data
505 THE I<CHECK> argument is used as follows. When you omit it, it is
506 identical to I<CHECK> = 0.
508 =item I<CHECK> = Encode::FB_DEFAULT ( == 0)
510 If I<CHECK> is 0, (en|de)code will put I<substitution character> in
511 place of the malformed character. for UCM-based encodings,
512 E<lt>subcharE<gt> will be used. For Unicode, \xFFFD is used. If the
513 data is supposed to be UTF-8, an optional lexical warning (category
516 =item I<CHECK> = Encode::DIE_ON_ERROR (== 1)
518 If I<CHECK> is 1, methods will die immediately with an error
519 message. so when I<CHECK> is set, you should trap the fatal error
520 with eval{} unless you really want to let it die on error.
522 =item I<CHECK> = Encode::FB_QUIET
524 If I<CHECK> is set to Encode::FB_QUIET, (en|de)code will immediately
525 return processed part on error, with data passed via argument
526 overwritten with unprocessed part. This is handy when have to
527 repeatedly call because the source data is chopped in the middle for
528 some reasons, such as fixed-width buffer. Here is a sample code that
532 while(defined(read $fh, $buffer, 256)){
533 # buffer may end in partial character so we append
535 $utf8 .= decode($encoding, $data, ENCODE::FB_QUIET);
536 # $data now contains unprocessed partial character
539 =item I<CHECK> = Encode::FB_WARN
541 This is the same as above, except it warns on error. Handy when you
542 are debugging the mode above.
544 =item perlqq mode (I<CHECK> = Encode::FB_PERLQQ)
546 For encodings that are implemented by Encode::XS, CHECK ==
547 Encode::FB_PERLQQ turns (en|de)code into C<perlqq> fallback mode.
549 When you decode, '\xI<XX>' will be placed where I<XX> is the hex
550 representation of the octet that could not be decoded to utf8. And
551 when you encode, '\x{I<xxxx>}' will be placed where I<xxxx> is the
552 Unicode ID of the character that cannot be found in the character
553 repertoire of the encoding.
557 These modes are actually set via bitmask. here is how FB_XX are laid
558 out. for FB_XX you can import via C<use Encode qw(:fallbacks)> for
559 generic bitmask constants, you can import via
560 C<use Encode qw(:fallback_all)>.
562 FB_DEFAULT FB_CROAK FB_QUIET FB_WARN FB_PERLQQ
565 RETURN_ON_ERR 0x0004 X X
569 =head2 Unemplemented fallback schemes
571 In future you will be able to use a code reference to a callback
572 function for the value of I<CHECK> but its API is still undecided.
574 =head1 Defining Encodings
576 To define a new encoding, use:
578 use Encode qw(define_alias);
579 define_encoding($object, 'canonicalName' [, alias...]);
581 I<canonicalName> will be associated with I<$object>. The object
582 should provide the interface described in L<Encode::Encoding>
583 If more than two arguments are provided then additional
584 arguments are taken as aliases for I<$object> as for C<define_alias>.
586 See L<Encode::Encoding> for more details.
588 =head1 Messing with Perl's Internals
590 The following API uses parts of Perl's internals in the current
591 implementation. As such they are efficient, but may change.
595 =item is_utf8(STRING [, CHECK])
597 [INTERNAL] Test whether the UTF-8 flag is turned on in the STRING.
598 If CHECK is true, also checks the data in STRING for being well-formed
599 UTF-8. Returns true if successful, false otherwise.
601 =item _utf8_on(STRING)
603 [INTERNAL] Turn on the UTF-8 flag in STRING. The data in STRING is
604 B<not> checked for being well-formed UTF-8. Do not use unless you
605 B<know> that the STRING is well-formed UTF-8. Returns the previous
606 state of the UTF-8 flag (so please don't test the return value as
607 I<not> success or failure), or C<undef> if STRING is not a string.
609 =item _utf8_off(STRING)
611 [INTERNAL] Turn off the UTF-8 flag in STRING. Do not use frivolously.
612 Returns the previous state of the UTF-8 flag (so please don't test the
613 return value as I<not> success or failure), or C<undef> if STRING is
621 L<Encode::Supported>,
628 the Perl Unicode Mailing List E<lt>perl-unicode@perl.orgE<gt>
632 This project was originated by Nick Ing-Simmons and later maintained
633 by Dan Kogai E<lt>dankogai@dan.co.jpE<gt>. See AUTHORS for full list
634 of people involved. For any questions, use
635 E<lt>perl-unicode@perl.orgE<gt> so others can share.