Commit | Line | Data |
2c674647 |
1 | package Encode; |
51ef4e11 |
2 | use strict; |
b2704119 |
3 | our $VERSION = do { my @r = (q$Revision: 1.42 $ =~ /\d+/g); sprintf "%d."."%02d" x $#r, @r }; |
5129552c |
4 | our $DEBUG = 0; |
2c674647 |
5 | |
6 | require DynaLoader; |
7 | require Exporter; |
8 | |
51ef4e11 |
9 | our @ISA = qw(Exporter DynaLoader); |
2c674647 |
10 | |
4411f3b6 |
11 | # Public, encouraged API is exported by default |
51ef4e11 |
12 | our @EXPORT = qw ( |
4411f3b6 |
13 | decode |
4411f3b6 |
14 | decode_utf8 |
fcb875d4 |
15 | encode |
16 | encode_utf8 |
51ef4e11 |
17 | encodings |
fcb875d4 |
18 | find_encoding |
4411f3b6 |
19 | ); |
20 | |
51ef4e11 |
21 | our @EXPORT_OK = |
2c674647 |
22 | qw( |
fcb875d4 |
23 | _utf8_off |
24 | _utf8_on |
51ef4e11 |
25 | define_encoding |
2c674647 |
26 | from_to |
4411f3b6 |
27 | is_16bit |
fcb875d4 |
28 | is_8bit |
29 | is_utf8 |
30 | resolve_alias |
a12c0f56 |
31 | utf8_downgrade |
fcb875d4 |
32 | utf8_upgrade |
2c674647 |
33 | ); |
34 | |
35 | bootstrap Encode (); |
36 | |
4411f3b6 |
37 | # Documentation moved after __END__ for speed - NI-S |
2c674647 |
38 | |
bf230f3d |
39 | use Carp; |
40 | |
a63c962f |
41 | our $ON_EBCDIC = (ord("A") == 193); |
f2a2953c |
42 | |
5d030b67 |
43 | use Encode::Alias; |
44 | |
5129552c |
45 | # Make a %Encoding package variable to allow a certain amount of cheating |
46 | our %Encoding; |
aae85ceb |
47 | our %ExtModule; |
48 | require Encode::Config; |
49 | eval { require Encode::ConfigLocal }; |
5129552c |
50 | |
656753f8 |
51 | sub encodings |
52 | { |
5129552c |
53 | my $class = shift; |
071db25d |
54 | my @modules = (@_ and $_[0] eq ":all") ? values %ExtModule : @_; |
c731e18e |
55 | for my $mod (@modules){ |
56 | $mod =~ s,::,/,g or $mod = "Encode/$mod"; |
57 | $mod .= '.pm'; |
58 | $DEBUG and warn "about to require $mod;"; |
59 | eval { require $mod; }; |
5129552c |
60 | } |
c731e18e |
61 | my %modules = map {$_ => 1} @modules; |
5129552c |
62 | return |
ce912cd4 |
63 | sort { lc $a cmp lc $b } |
64 | grep {!/^(?:Internal|Unicode)$/o} keys %Encoding; |
51ef4e11 |
65 | } |
66 | |
51ef4e11 |
67 | sub define_encoding |
68 | { |
18586f54 |
69 | my $obj = shift; |
70 | my $name = shift; |
5129552c |
71 | $Encoding{$name} = $obj; |
18586f54 |
72 | my $lc = lc($name); |
73 | define_alias($lc => $obj) unless $lc eq $name; |
74 | while (@_) |
75 | { |
76 | my $alias = shift; |
77 | define_alias($alias,$obj); |
78 | } |
79 | return $obj; |
656753f8 |
80 | } |
81 | |
656753f8 |
82 | sub getEncoding |
83 | { |
dd9703c9 |
84 | my ($class,$name,$skip_external) = @_; |
18586f54 |
85 | my $enc; |
86 | if (ref($name) && $name->can('new_sequence')) |
87 | { |
88 | return $name; |
89 | } |
90 | my $lc = lc $name; |
5129552c |
91 | if (exists $Encoding{$name}) |
18586f54 |
92 | { |
5129552c |
93 | return $Encoding{$name}; |
18586f54 |
94 | } |
5129552c |
95 | if (exists $Encoding{$lc}) |
18586f54 |
96 | { |
5129552c |
97 | return $Encoding{$lc}; |
18586f54 |
98 | } |
c50d192e |
99 | |
5129552c |
100 | my $oc = $class->find_alias($name); |
c50d192e |
101 | return $oc if defined $oc; |
102 | |
5129552c |
103 | $oc = $class->find_alias($lc) if $lc ne $name; |
c50d192e |
104 | return $oc if defined $oc; |
105 | |
c731e18e |
106 | unless ($skip_external) |
d1ed7747 |
107 | { |
c731e18e |
108 | if (my $mod = $ExtModule{$name} || $ExtModule{$lc}){ |
109 | $mod =~ s,::,/,g ; $mod .= '.pm'; |
110 | eval{ require $mod; }; |
111 | return $Encoding{$name} if exists $Encoding{$name}; |
112 | } |
d1ed7747 |
113 | } |
18586f54 |
114 | return; |
656753f8 |
115 | } |
116 | |
4411f3b6 |
117 | sub find_encoding |
118 | { |
dd9703c9 |
119 | my ($name,$skip_external) = @_; |
120 | return __PACKAGE__->getEncoding($name,$skip_external); |
4411f3b6 |
121 | } |
122 | |
fcb875d4 |
123 | sub resolve_alias { |
124 | my $obj = find_encoding(shift); |
125 | defined $obj and return $obj->name; |
126 | return; |
127 | } |
128 | |
b2704119 |
129 | sub encode($$;$) |
4411f3b6 |
130 | { |
18586f54 |
131 | my ($name,$string,$check) = @_; |
b2704119 |
132 | $check ||=0; |
18586f54 |
133 | my $enc = find_encoding($name); |
134 | croak("Unknown encoding '$name'") unless defined $enc; |
135 | my $octets = $enc->encode($string,$check); |
136 | return undef if ($check && length($string)); |
137 | return $octets; |
4411f3b6 |
138 | } |
139 | |
b2704119 |
140 | sub decode($$;$) |
4411f3b6 |
141 | { |
18586f54 |
142 | my ($name,$octets,$check) = @_; |
b2704119 |
143 | $check ||=0; |
18586f54 |
144 | my $enc = find_encoding($name); |
145 | croak("Unknown encoding '$name'") unless defined $enc; |
146 | my $string = $enc->decode($octets,$check); |
147 | $_[1] = $octets if $check; |
148 | return $string; |
4411f3b6 |
149 | } |
150 | |
b2704119 |
151 | sub from_to($$$;$) |
4411f3b6 |
152 | { |
18586f54 |
153 | my ($string,$from,$to,$check) = @_; |
b2704119 |
154 | $check ||=0; |
18586f54 |
155 | my $f = find_encoding($from); |
156 | croak("Unknown encoding '$from'") unless defined $f; |
157 | my $t = find_encoding($to); |
158 | croak("Unknown encoding '$to'") unless defined $t; |
159 | my $uni = $f->decode($string,$check); |
160 | return undef if ($check && length($string)); |
a999c27c |
161 | $string = $t->encode($uni,$check); |
18586f54 |
162 | return undef if ($check && length($uni)); |
3ef515df |
163 | return defined($_[0] = $string) ? length($string) : undef ; |
4411f3b6 |
164 | } |
165 | |
b2704119 |
166 | sub encode_utf8($) |
4411f3b6 |
167 | { |
18586f54 |
168 | my ($str) = @_; |
c731e18e |
169 | utf8::encode($str); |
18586f54 |
170 | return $str; |
4411f3b6 |
171 | } |
172 | |
b2704119 |
173 | sub decode_utf8($) |
4411f3b6 |
174 | { |
18586f54 |
175 | my ($str) = @_; |
176 | return undef unless utf8::decode($str); |
177 | return $str; |
5ad8ef52 |
178 | } |
179 | |
f2a2953c |
180 | predefine_encodings(); |
181 | |
182 | # |
183 | # This is to restore %Encoding if really needed; |
184 | # |
185 | sub predefine_encodings{ |
186 | if ($ON_EBCDIC) { |
187 | # was in Encode::UTF_EBCDIC |
188 | package Encode::UTF_EBCDIC; |
189 | *name = sub{ shift->{'Name'} }; |
190 | *new_sequence = sub{ return $_[0] }; |
191 | *decode = sub{ |
192 | my ($obj,$str,$chk) = @_; |
193 | my $res = ''; |
194 | for (my $i = 0; $i < length($str); $i++) { |
195 | $res .= |
196 | chr(utf8::unicode_to_native(ord(substr($str,$i,1)))); |
197 | } |
198 | $_[1] = '' if $chk; |
199 | return $res; |
200 | }; |
201 | *encode = sub{ |
202 | my ($obj,$str,$chk) = @_; |
203 | my $res = ''; |
204 | for (my $i = 0; $i < length($str); $i++) { |
205 | $res .= |
206 | chr(utf8::native_to_unicode(ord(substr($str,$i,1)))); |
207 | } |
208 | $_[1] = '' if $chk; |
209 | return $res; |
210 | }; |
77ea6967 |
211 | $Encode::Encoding{Unicode} = |
c731e18e |
212 | bless {Name => "UTF_EBCDIC"} => "Encode::UTF_EBCDIC"; |
f2a2953c |
213 | } else { |
214 | # was in Encode::UTF_EBCDIC |
215 | package Encode::Internal; |
216 | *name = sub{ shift->{'Name'} }; |
217 | *new_sequence = sub{ return $_[0] }; |
218 | *decode = sub{ |
219 | my ($obj,$str,$chk) = @_; |
220 | utf8::upgrade($str); |
221 | $_[1] = '' if $chk; |
222 | return $str; |
223 | }; |
224 | *encode = \&decode; |
225 | $Encode::Encoding{Unicode} = |
c731e18e |
226 | bless {Name => "Internal"} => "Encode::Internal"; |
f2a2953c |
227 | } |
228 | |
229 | { |
230 | # was in Encode::utf8 |
231 | package Encode::utf8; |
232 | *name = sub{ shift->{'Name'} }; |
233 | *new_sequence = sub{ return $_[0] }; |
234 | *decode = sub{ |
235 | my ($obj,$octets,$chk) = @_; |
236 | my $str = Encode::decode_utf8($octets); |
237 | if (defined $str) { |
238 | $_[1] = '' if $chk; |
239 | return $str; |
240 | } |
241 | return undef; |
242 | }; |
243 | *encode = sub { |
244 | my ($obj,$string,$chk) = @_; |
245 | my $octets = Encode::encode_utf8($string); |
246 | $_[1] = '' if $chk; |
247 | return $octets; |
248 | }; |
249 | $Encode::Encoding{utf8} = |
c731e18e |
250 | bless {Name => "utf8"} => "Encode::utf8"; |
f2a2953c |
251 | } |
f2a2953c |
252 | } |
253 | |
18586f54 |
254 | require Encode::Encoding; |
b2704119 |
255 | |
256 | eval { require PerlIO::encoding }; |
4411f3b6 |
257 | |
656753f8 |
258 | 1; |
259 | |
2a936312 |
260 | __END__ |
261 | |
4411f3b6 |
262 | =head1 NAME |
263 | |
264 | Encode - character encodings |
265 | |
266 | =head1 SYNOPSIS |
267 | |
268 | use Encode; |
269 | |
67d7b5ef |
270 | |
271 | =head2 Table of Contents |
272 | |
273 | Encode consists of a collection of modules which details are too big |
274 | to fit in one document. This POD itself explains the top-level APIs |
275 | and general topics at a glance. For other topics and more details, |
276 | see the PODs below; |
277 | |
278 | Name Description |
279 | -------------------------------------------------------- |
280 | Encode::Alias Alias defintions to encodings |
281 | Encode::Encoding Encode Implementation Base Class |
282 | Encode::Supported List of Supported Encodings |
283 | Encode::CN Simplified Chinese Encodings |
284 | Encode::JP Japanese Encodings |
285 | Encode::KR Korean Encodings |
286 | Encode::TW Traditional Chinese Encodings |
287 | -------------------------------------------------------- |
288 | |
4411f3b6 |
289 | =head1 DESCRIPTION |
290 | |
47bfe92f |
291 | The C<Encode> module provides the interfaces between Perl's strings |
67d7b5ef |
292 | and the rest of the system. Perl strings are sequences of |
293 | B<characters>. |
294 | |
295 | The repertoire of characters that Perl can represent is at least that |
296 | defined by the Unicode Consortium. On most platforms the ordinal |
297 | values of the characters (as returned by C<ord(ch)>) is the "Unicode |
298 | codepoint" for the character (the exceptions are those platforms where |
299 | the legacy encoding is some variant of EBCDIC rather than a super-set |
300 | of ASCII - see L<perlebcdic>). |
301 | |
302 | Traditionally computer data has been moved around in 8-bit chunks |
303 | often called "bytes". These chunks are also known as "octets" in |
304 | networking standards. Perl is widely used to manipulate data of many |
305 | types - not only strings of characters representing human or computer |
306 | languages but also "binary" data being the machines representation of |
307 | numbers, pixels in an image - or just about anything. |
308 | |
309 | When Perl is processing "binary data" the programmer wants Perl to |
310 | process "sequences of bytes". This is not a problem for Perl - as a |
311 | byte has 256 possible values it easily fits in Perl's much larger |
312 | "logical character". |
313 | |
314 | =head2 TERMINOLOGY |
4411f3b6 |
315 | |
67d7b5ef |
316 | =over 4 |
21938dfa |
317 | |
67d7b5ef |
318 | =item * |
319 | |
320 | I<character>: a character in the range 0..(2**32-1) (or more). |
321 | (What Perl's strings are made of.) |
322 | |
323 | =item * |
324 | |
325 | I<byte>: a character in the range 0..255 |
326 | (A special case of a Perl character.) |
327 | |
328 | =item * |
329 | |
330 | I<octet>: 8 bits of data, with ordinal values 0..255 |
331 | (Term for bytes passed to or from a non-Perl context, e.g. disk file.) |
332 | |
333 | =back |
4411f3b6 |
334 | |
67d7b5ef |
335 | The marker [INTERNAL] marks Internal Implementation Details, in |
336 | general meant only for those who think they know what they are doing, |
337 | and such details may change in future releases. |
338 | |
339 | =head1 PERL ENCODING API |
4411f3b6 |
340 | |
341 | =over 4 |
342 | |
f2a2953c |
343 | =item $octets = encode(ENCODING, $string[, CHECK]) |
4411f3b6 |
344 | |
47bfe92f |
345 | Encodes string from Perl's internal form into I<ENCODING> and returns |
67d7b5ef |
346 | a sequence of octets. ENCODING can be either a canonical name or |
347 | alias. For encoding names and aliases, see L</"Defining Aliases">. |
348 | For CHECK see L</"Handling Malformed Data">. |
4411f3b6 |
349 | |
67d7b5ef |
350 | For example to convert (internally UTF-8 encoded) Unicode string to |
351 | iso-8859-1 (also known as Latin1), |
681a7c68 |
352 | |
67d7b5ef |
353 | $octets = encode("iso-8859-1", $unicode); |
681a7c68 |
354 | |
f2a2953c |
355 | =item $string = decode(ENCODING, $octets[, CHECK]) |
4411f3b6 |
356 | |
47bfe92f |
357 | Decode sequence of octets assumed to be in I<ENCODING> into Perl's |
67d7b5ef |
358 | internal form and returns the resulting string. as in encode(), |
359 | ENCODING can be either a canonical name or alias. For encoding names |
360 | and aliases, see L</"Defining Aliases">. For CHECK see |
47bfe92f |
361 | L</"Handling Malformed Data">. |
362 | |
1b2c56c8 |
363 | For example to convert ISO-8859-1 data to UTF-8: |
681a7c68 |
364 | |
67d7b5ef |
365 | $utf8 = decode("iso-8859-1", $latin1); |
681a7c68 |
366 | |
f2a2953c |
367 | =item [$length =] from_to($string, FROM_ENCODING, TO_ENCODING [,CHECK]) |
47bfe92f |
368 | |
2b106fbe |
369 | Convert B<in-place> the data between two encodings. How did the data |
370 | in $string originally get to be in FROM_ENCODING? Either using |
67d7b5ef |
371 | encode() or through PerlIO: See L</"Encoding and IO">. |
372 | For encoding names and aliases, see L</"Defining Aliases">. |
373 | For CHECK see L</"Handling Malformed Data">. |
2b106fbe |
374 | |
1b2c56c8 |
375 | For example to convert ISO-8859-1 data to UTF-8: |
2b106fbe |
376 | |
377 | from_to($data, "iso-8859-1", "utf-8"); |
378 | |
379 | and to convert it back: |
380 | |
381 | from_to($data, "utf-8", "iso-8859-1"); |
4411f3b6 |
382 | |
ab97ca19 |
383 | Note that because the conversion happens in place, the data to be |
384 | converted cannot be a string constant, it must be a scalar variable. |
385 | |
3ef515df |
386 | from_to() return the length of the converted string on success, undef |
387 | otherwise. |
388 | |
4411f3b6 |
389 | =back |
390 | |
f2a2953c |
391 | =head2 UTF-8 / utf8 |
392 | |
393 | The Unicode consortium defines the UTF-8 standard as a way of encoding |
394 | the entire Unicode repertoire as sequences of octets. This encoding is |
395 | expected to become very widespread. Perl can use this form internally |
396 | to represent strings, so conversions to and from this form are |
397 | particularly efficient (as octets in memory do not have to change, |
398 | just the meta-data that tells Perl how to treat them). |
399 | |
400 | =over 4 |
401 | |
402 | =item $octets = encode_utf8($string); |
403 | |
404 | The characters that comprise string are encoded in Perl's superset of UTF-8 |
405 | and the resulting octets returned as a sequence of bytes. All possible |
406 | characters have a UTF-8 representation so this function cannot fail. |
407 | |
408 | =item $string = decode_utf8($octets [, CHECK]); |
409 | |
410 | The sequence of octets represented by $octets is decoded from UTF-8 |
411 | into a sequence of logical characters. Not all sequences of octets |
412 | form valid UTF-8 encodings, so it is possible for this call to fail. |
413 | For CHECK see L</"Handling Malformed Data">. |
414 | |
415 | =back |
416 | |
51ef4e11 |
417 | =head2 Listing available encodings |
418 | |
5129552c |
419 | use Encode; |
420 | @list = Encode->encodings(); |
421 | |
422 | Returns a list of the canonical names of the available encodings that |
423 | are loaded. To get a list of all available encodings including the |
424 | ones that are not loaded yet, say |
425 | |
426 | @all_encodings = Encode->encodings(":all"); |
427 | |
428 | Or you can give the name of specific module. |
429 | |
c731e18e |
430 | @with_jp = Encode->encodings("Encode::JP"); |
431 | |
432 | When "::" is not in the name, "Encode::" is assumed. |
51ef4e11 |
433 | |
c731e18e |
434 | @ebcdic = Encode->encodings("EBCDIC"); |
5d030b67 |
435 | |
a63c962f |
436 | To find which encodings are supported by this package in details, |
5d030b67 |
437 | see L<Encode::Supported>. |
51ef4e11 |
438 | |
439 | =head2 Defining Aliases |
440 | |
67d7b5ef |
441 | To add new alias to a given encoding, Use; |
442 | |
5129552c |
443 | use Encode; |
444 | use Encode::Alias; |
a63c962f |
445 | define_alias(newName => ENCODING); |
51ef4e11 |
446 | |
3ef515df |
447 | After that, newName can be used as an alias for ENCODING. |
f2a2953c |
448 | ENCODING may be either the name of an encoding or an |
449 | I<encoding object> |
51ef4e11 |
450 | |
fcb875d4 |
451 | But before you do so, make sure the alias is nonexistent with |
452 | C<resolve_alias()>, which returns the canonical name thereof. |
453 | i.e. |
454 | |
455 | Encode::resolve_alias("latin1") eq "iso-8859-1" # true |
456 | Encode::resolve_alias("iso-8859-12") # false; nonexistent |
457 | Encode::resolve_alias($name) eq $name # true if $name is canonical |
458 | |
459 | This resolve_alias() does not need C<use Encode::Alias> and is |
460 | exported via C<use encode qw(resolve_alias)>. |
461 | |
5d030b67 |
462 | See L<Encode::Alias> on details. |
51ef4e11 |
463 | |
4411f3b6 |
464 | =head1 Encoding and IO |
465 | |
466 | It is very common to want to do encoding transformations when |
467 | reading or writing files, network connections, pipes etc. |
47bfe92f |
468 | If Perl is configured to use the new 'perlio' IO system then |
4411f3b6 |
469 | C<Encode> provides a "layer" (See L<perliol>) which can transform |
470 | data as it is read or written. |
471 | |
8e86646e |
472 | Here is how the blind poet would modernise the encoding: |
473 | |
42234700 |
474 | use Encode; |
8e86646e |
475 | open(my $iliad,'<:encoding(iso-8859-7)','iliad.greek'); |
476 | open(my $utf8,'>:utf8','iliad.utf8'); |
477 | my @epic = <$iliad>; |
478 | print $utf8 @epic; |
479 | close($utf8); |
480 | close($illiad); |
4411f3b6 |
481 | |
482 | In addition the new IO system can also be configured to read/write |
483 | UTF-8 encoded characters (as noted above this is efficient): |
484 | |
e9692b5b |
485 | open(my $fh,'>:utf8','anything'); |
486 | print $fh "Any \x{0021} string \N{SMILEY FACE}\n"; |
4411f3b6 |
487 | |
488 | Either of the above forms of "layer" specifications can be made the default |
489 | for a lexical scope with the C<use open ...> pragma. See L<open>. |
490 | |
491 | Once a handle is open is layers can be altered using C<binmode>. |
492 | |
47bfe92f |
493 | Without any such configuration, or if Perl itself is built using |
4411f3b6 |
494 | system's own IO, then write operations assume that file handle accepts |
495 | only I<bytes> and will C<die> if a character larger than 255 is |
496 | written to the handle. When reading, each octet from the handle |
497 | becomes a byte-in-a-character. Note that this default is the same |
47bfe92f |
498 | behaviour as bytes-only languages (including Perl before v5.6) would |
499 | have, and is sufficient to handle native 8-bit encodings |
500 | e.g. iso-8859-1, EBCDIC etc. and any legacy mechanisms for handling |
501 | other encodings and binary data. |
502 | |
503 | In other cases it is the programs responsibility to transform |
504 | characters into bytes using the API above before doing writes, and to |
505 | transform the bytes read from a handle into characters before doing |
506 | "character operations" (e.g. C<lc>, C</\W+/>, ...). |
507 | |
47bfe92f |
508 | You can also use PerlIO to convert larger amounts of data you don't |
1b2c56c8 |
509 | want to bring into memory. For example to convert between ISO-8859-1 |
47bfe92f |
510 | (Latin 1) and UTF-8 (or UTF-EBCDIC in EBCDIC machines): |
511 | |
e9692b5b |
512 | open(F, "<:encoding(iso-8859-1)", "data.txt") or die $!; |
513 | open(G, ">:utf8", "data.utf") or die $!; |
514 | while (<F>) { print G } |
515 | |
516 | # Could also do "print G <F>" but that would pull |
517 | # the whole file into memory just to write it out again. |
518 | |
519 | More examples: |
47bfe92f |
520 | |
e9692b5b |
521 | open(my $f, "<:encoding(cp1252)") |
522 | open(my $g, ">:encoding(iso-8859-2)") |
523 | open(my $h, ">:encoding(latin9)") # iso-8859-15 |
47bfe92f |
524 | |
525 | See L<PerlIO> for more information. |
4411f3b6 |
526 | |
1768d7eb |
527 | See also L<encoding> for how to change the default encoding of the |
d521382b |
528 | data in your script. |
1768d7eb |
529 | |
67d7b5ef |
530 | =head1 Handling Malformed Data |
531 | |
f2a2953c |
532 | If I<CHECK> is not set, (en|de)code will put I<substitution character> in |
533 | place of the malformed character. for UCM-based encodings, |
534 | E<lt>subcharE<gt> will be used. For Unicode, \xFFFD is used. If the |
535 | data is supposed to be UTF-8, an optional lexical warning (category |
536 | utf8) is given. |
67d7b5ef |
537 | |
f2a2953c |
538 | If I<CHECK> is true but not a code reference, dies with an error message. |
67d7b5ef |
539 | |
f2a2953c |
540 | In future you will be able to use a code reference to a callback |
541 | function for the value of I<CHECK> but its API is still undecided. |
67d7b5ef |
542 | |
543 | =head1 Defining Encodings |
544 | |
545 | To define a new encoding, use: |
546 | |
547 | use Encode qw(define_alias); |
548 | define_encoding($object, 'canonicalName' [, alias...]); |
549 | |
550 | I<canonicalName> will be associated with I<$object>. The object |
551 | should provide the interface described in L<Encode::Encoding> |
552 | If more than two arguments are provided then additional |
553 | arguments are taken as aliases for I<$object> as for C<define_alias>. |
554 | |
f2a2953c |
555 | See L<Encode::Encoding> for more details. |
556 | |
4411f3b6 |
557 | =head1 Messing with Perl's Internals |
558 | |
47bfe92f |
559 | The following API uses parts of Perl's internals in the current |
560 | implementation. As such they are efficient, but may change. |
4411f3b6 |
561 | |
562 | =over 4 |
563 | |
a63c962f |
564 | =item is_utf8(STRING [, CHECK]) |
4411f3b6 |
565 | |
566 | [INTERNAL] Test whether the UTF-8 flag is turned on in the STRING. |
47bfe92f |
567 | If CHECK is true, also checks the data in STRING for being well-formed |
568 | UTF-8. Returns true if successful, false otherwise. |
4411f3b6 |
569 | |
a63c962f |
570 | =item _utf8_on(STRING) |
4411f3b6 |
571 | |
572 | [INTERNAL] Turn on the UTF-8 flag in STRING. The data in STRING is |
573 | B<not> checked for being well-formed UTF-8. Do not use unless you |
574 | B<know> that the STRING is well-formed UTF-8. Returns the previous |
575 | state of the UTF-8 flag (so please don't test the return value as |
576 | I<not> success or failure), or C<undef> if STRING is not a string. |
577 | |
a63c962f |
578 | =item _utf8_off(STRING) |
4411f3b6 |
579 | |
580 | [INTERNAL] Turn off the UTF-8 flag in STRING. Do not use frivolously. |
581 | Returns the previous state of the UTF-8 flag (so please don't test the |
582 | return value as I<not> success or failure), or C<undef> if STRING is |
583 | not a string. |
584 | |
585 | =back |
586 | |
587 | =head1 SEE ALSO |
588 | |
5d030b67 |
589 | L<Encode::Encoding>, |
590 | L<Encode::Supported>, |
591 | L<PerlIO>, |
592 | L<encoding>, |
593 | L<perlebcdic>, |
594 | L<perlfunc/open>, |
595 | L<perlunicode>, |
596 | L<utf8>, |
597 | the Perl Unicode Mailing List E<lt>perl-unicode@perl.orgE<gt> |
4411f3b6 |
598 | |
aae85ceb |
599 | head2 MAINTAINER |
600 | |
601 | This project was originated by Nick Ing-Simmons and later maintained |
602 | by Dan Kogai E<lt>dankogai@dan.co.jpE<gt>. See AUTHORS for full list |
603 | of people involved. For any questions, use |
604 | E<lt>perl-unicode@perl.orgE<gt> so others can share. |
605 | |
4411f3b6 |
606 | =cut |