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423cee85 |
1 | package charnames; |
b177ca84 |
2 | use strict; |
3 | use warnings; |
51cf30b6 |
4 | use File::Spec; |
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5 | our $VERSION = '1.05'; |
b75c8c73 |
6 | |
d5448623 |
7 | use bytes (); # for $bytes::hint_bits |
9cfe5470 |
8 | $charnames::hint_bits = 0x20000; # HINT_LOCALIZE_HH |
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9 | |
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10 | my %alias1 = ( |
11 | # Icky 3.2 names with parentheses. |
12 | 'LINE FEED' => 'LINE FEED (LF)', |
13 | 'FORM FEED' => 'FORM FEED (FF)', |
14 | 'CARRIAGE RETURN' => 'CARRIAGE RETURN (CR)', |
15 | 'NEXT LINE' => 'NEXT LINE (NEL)', |
16 | # Convenience. |
17 | 'LF' => 'LINE FEED (LF)', |
18 | 'FF' => 'FORM FEED (FF)', |
eb380778 |
19 | 'CR' => 'CARRIAGE RETURN (CR)', |
51e9e896 |
20 | 'NEL' => 'NEXT LINE (NEL)', |
24b5d5cc |
21 | # More convenience. For futher convencience, |
22 | # it is suggested some way using using the NamesList |
23 | # aliases is implemented. |
24 | 'ZWNJ' => 'ZERO WIDTH NON-JOINER', |
25 | 'ZWJ' => 'ZERO WIDTH JOINER', |
52ea3e69 |
26 | 'BOM' => 'BYTE ORDER MARK', |
27 | ); |
28 | |
29 | my %alias2 = ( |
30 | # Pre-3.2 compatibility (only for the first 256 characters). |
31 | 'HORIZONTAL TABULATION' => 'CHARACTER TABULATION', |
32 | 'VERTICAL TABULATION' => 'LINE TABULATION', |
33 | 'FILE SEPARATOR' => 'INFORMATION SEPARATOR FOUR', |
34 | 'GROUP SEPARATOR' => 'INFORMATION SEPARATOR THREE', |
35 | 'RECORD SEPARATOR' => 'INFORMATION SEPARATOR TWO', |
36 | 'UNIT SEPARATOR' => 'INFORMATION SEPARATOR ONE', |
37 | 'PARTIAL LINE DOWN' => 'PARTIAL LINE FORWARD', |
38 | 'PARTIAL LINE UP' => 'PARTIAL LINE BACKWARD', |
39 | ); |
40 | |
35c0985d |
41 | my %alias3 = ( |
42 | # User defined aliasses. Even more convenient :) |
43 | ); |
423cee85 |
44 | my $txt; |
45 | |
8878f897 |
46 | sub croak |
47 | { |
48 | require Carp; goto &Carp::croak; |
49 | } # croak |
50 | |
51 | sub carp |
52 | { |
53 | require Carp; goto &Carp::carp; |
54 | } # carp |
55 | |
35c0985d |
56 | sub alias (@) |
57 | { |
58 | @_ or return %alias3; |
59 | my $alias = ref $_[0] ? $_[0] : { @_ }; |
60 | @alias3{keys %$alias} = values %$alias; |
61 | } # alias |
62 | |
63 | sub alias_file ($) |
64 | { |
51cf30b6 |
65 | my ($arg, $file) = @_; |
66 | if (-f $arg && File::Spec->file_name_is_absolute ($arg)) { |
67 | $file = $arg; |
68 | } |
69 | elsif ($arg =~ m/^\w+$/) { |
70 | $file = "unicore/${arg}_alias.pl"; |
71 | } |
72 | else { |
73 | croak "Charnames alias files can only have identifier characters"; |
74 | } |
35c0985d |
75 | if (my @alias = do $file) { |
51cf30b6 |
76 | @alias == 1 && !defined $alias[0] and |
77 | croak "$file cannot be used as alias file for charnames"; |
78 | @alias % 2 and |
79 | croak "$file did not return a (valid) list of alias pairs"; |
35c0985d |
80 | alias (@alias); |
81 | return (1); |
82 | } |
83 | 0; |
84 | } # alias_file |
85 | |
423cee85 |
86 | # This is not optimized in any way yet |
b177ca84 |
87 | sub charnames |
88 | { |
89 | my $name = shift; |
90 | |
52ea3e69 |
91 | if (exists $alias1{$name}) { |
35c0985d |
92 | $name = $alias1{$name}; |
52ea3e69 |
93 | } |
35c0985d |
94 | elsif (exists $alias2{$name}) { |
95 | require warnings; |
96 | warnings::warnif('deprecated', qq{Unicode character name "$name" is deprecated, use "$alias2{$name}" instead}); |
97 | $name = $alias2{$name}; |
98 | } |
99 | elsif (exists $alias3{$name}) { |
100 | $name = $alias3{$name}; |
52ea3e69 |
101 | } |
b177ca84 |
102 | |
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103 | my $ord; |
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104 | my @off; |
52ea3e69 |
105 | my $fname; |
106 | |
107 | if ($name eq "BYTE ORDER MARK") { |
35c0985d |
108 | $fname = $name; |
109 | $ord = 0xFEFF; |
52ea3e69 |
110 | } else { |
35c0985d |
111 | ## Suck in the code/name list as a big string. |
112 | ## Lines look like: |
113 | ## "0052\t\tLATIN CAPITAL LETTER R\n" |
114 | $txt = do "unicore/Name.pl" unless $txt; |
115 | |
116 | ## @off will hold the index into the code/name string of the start and |
117 | ## end of the name as we find it. |
118 | |
a6d05634 |
119 | ## If :full, look for the name exactly |
35c0985d |
120 | if ($^H{charnames_full} and $txt =~ /\t\t\Q$name\E$/m) { |
121 | @off = ($-[0], $+[0]); |
122 | } |
123 | |
124 | ## If we didn't get above, and :short allowed, look for the short name. |
125 | ## The short name is like "greek:Sigma" |
126 | unless (@off) { |
127 | if ($^H{charnames_short} and $name =~ /^(.+?):(.+)/s) { |
128 | my ($script, $cname) = ($1, $2); |
129 | my $case = $cname =~ /[[:upper:]]/ ? "CAPITAL" : "SMALL"; |
130 | if ($txt =~ m/\t\t\U$script\E (?:$case )?LETTER \U\Q$cname\E$/m) { |
52ea3e69 |
131 | @off = ($-[0], $+[0]); |
35c0985d |
132 | } |
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133 | } |
35c0985d |
134 | } |
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135 | |
35c0985d |
136 | ## If we still don't have it, check for the name among the loaded |
137 | ## scripts. |
138 | if (not @off) { |
139 | my $case = $name =~ /[[:upper:]]/ ? "CAPITAL" : "SMALL"; |
140 | for my $script (@{$^H{charnames_scripts}}) { |
141 | if ($txt =~ m/\t\t$script (?:$case )?LETTER \U\Q$name\E$/m) { |
142 | @off = ($-[0], $+[0]); |
143 | last; |
144 | } |
52ea3e69 |
145 | } |
35c0985d |
146 | } |
147 | |
148 | ## If we don't have it by now, give up. |
149 | unless (@off) { |
150 | carp "Unknown charname '$name'"; |
151 | return "\x{FFFD}"; |
152 | } |
153 | |
154 | ## |
155 | ## Now know where in the string the name starts. |
156 | ## The code, in hex, is before that. |
157 | ## |
158 | ## The code can be 4-6 characters long, so we've got to sort of |
159 | ## go look for it, just after the newline that comes before $off[0]. |
160 | ## |
161 | ## This would be much easier if unicore/Name.pl had info in |
162 | ## a name/code order, instead of code/name order. |
163 | ## |
164 | ## The +1 after the rindex() is to skip past the newline we're finding, |
165 | ## or, if the rindex() fails, to put us to an offset of zero. |
166 | ## |
167 | my $hexstart = rindex($txt, "\n", $off[0]) + 1; |
168 | |
169 | ## we know where it starts, so turn into number - |
170 | ## the ordinal for the char. |
171 | $ord = hex substr($txt, $hexstart, $off[0] - $hexstart); |
423cee85 |
172 | } |
b177ca84 |
173 | |
d5448623 |
174 | if ($^H & $bytes::hint_bits) { # "use bytes" in effect? |
8058d7ab |
175 | use bytes; |
d41ff1b8 |
176 | return chr $ord if $ord <= 255; |
f0175764 |
177 | my $hex = sprintf "%04x", $ord; |
52ea3e69 |
178 | if (not defined $fname) { |
35c0985d |
179 | $fname = substr $txt, $off[0] + 2, $off[1] - $off[0] - 2; |
52ea3e69 |
180 | } |
f0175764 |
181 | croak "Character 0x$hex with name '$fname' is above 0xFF"; |
423cee85 |
182 | } |
f0175764 |
183 | |
52ea3e69 |
184 | no warnings 'utf8'; # allow even illegal characters |
bfa383d6 |
185 | return pack "U", $ord; |
35c0985d |
186 | } # charnames |
423cee85 |
187 | |
b177ca84 |
188 | sub import |
189 | { |
190 | shift; ## ignore class name |
191 | |
35c0985d |
192 | if (not @_) { |
193 | carp("`use charnames' needs explicit imports list"); |
b177ca84 |
194 | } |
d5448623 |
195 | $^H |= $charnames::hint_bits; |
423cee85 |
196 | $^H{charnames} = \&charnames ; |
b177ca84 |
197 | |
198 | ## |
199 | ## fill %h keys with our @_ args. |
200 | ## |
35c0985d |
201 | my ($promote, %h, @args) = (0); |
e5c3f898 |
202 | while (my $arg = shift) { |
203 | if ($arg eq ":alias") { |
51cf30b6 |
204 | @_ or |
205 | croak ":alias needs an argument in charnames"; |
35c0985d |
206 | my $alias = shift; |
207 | if (ref $alias) { |
208 | ref $alias eq "HASH" or |
51cf30b6 |
209 | croak "Only HASH reference supported as argument to :alias"; |
35c0985d |
210 | alias ($alias); |
211 | next; |
212 | } |
51cf30b6 |
213 | if ($alias =~ m{:(\w+)$}) { |
214 | $1 eq "full" || $1 eq "short" and |
215 | croak ":alias cannot use existing pragma :$1 (reversed order?)"; |
216 | alias_file ($1) and $promote = 1; |
217 | next; |
35c0985d |
218 | } |
51cf30b6 |
219 | alias_file ($alias); |
220 | next; |
221 | } |
e5c3f898 |
222 | if (substr($arg, 0, 1) eq ':' and ! ($arg eq ":full" || $arg eq ":short")) { |
223 | warn "unsupported special '$arg' in charnames"; |
51cf30b6 |
224 | next; |
35c0985d |
225 | } |
e5c3f898 |
226 | push @args, $arg; |
35c0985d |
227 | } |
228 | @args == 0 && $promote and @args = (":full"); |
229 | @h{@args} = (1) x @args; |
b177ca84 |
230 | |
423cee85 |
231 | $^H{charnames_full} = delete $h{':full'}; |
232 | $^H{charnames_short} = delete $h{':short'}; |
233 | $^H{charnames_scripts} = [map uc, keys %h]; |
b177ca84 |
234 | |
235 | ## |
236 | ## If utf8? warnings are enabled, and some scripts were given, |
237 | ## see if at least we can find one letter of each script. |
238 | ## |
35c0985d |
239 | if (warnings::enabled('utf8') && @{$^H{charnames_scripts}}) { |
240 | $txt = do "unicore/Name.pl" unless $txt; |
241 | |
242 | for my $script (@{$^H{charnames_scripts}}) { |
243 | if (not $txt =~ m/\t\t$script (?:CAPITAL |SMALL )?LETTER /) { |
244 | warnings::warn('utf8', "No such script: '$script'"); |
b177ca84 |
245 | } |
35c0985d |
246 | } |
bd62941a |
247 | } |
35c0985d |
248 | } # import |
423cee85 |
249 | |
4e2cda5d |
250 | my %viacode; |
251 | |
b177ca84 |
252 | sub viacode |
253 | { |
35c0985d |
254 | if (@_ != 1) { |
255 | carp "charnames::viacode() expects one argument"; |
bd5c3bd9 |
256 | return; |
35c0985d |
257 | } |
f0175764 |
258 | |
35c0985d |
259 | my $arg = shift; |
b177ca84 |
260 | |
bd5c3bd9 |
261 | # this comes actually from Unicode::UCD, where it is the named |
262 | # function _getcode (), but it avoids the overhead of loading it |
35c0985d |
263 | my $hex; |
bd5c3bd9 |
264 | if ($arg =~ /^[1-9]\d*$/) { |
35c0985d |
265 | $hex = sprintf "%04X", $arg; |
bd5c3bd9 |
266 | } elsif ($arg =~ /^(?:[Uu]\+|0[xX])?([[:xdigit:]]+)$/) { |
267 | $hex = $1; |
35c0985d |
268 | } else { |
269 | carp("unexpected arg \"$arg\" to charnames::viacode()"); |
270 | return; |
271 | } |
b177ca84 |
272 | |
bd5c3bd9 |
273 | # checking the length first is slightly faster |
274 | if (length($hex) > 5 && hex($hex) > 0x10FFFF) { |
35c0985d |
275 | carp sprintf "Unicode characters only allocated up to U+10FFFF (you asked for U+%X)", $hex; |
276 | return; |
277 | } |
f0175764 |
278 | |
35c0985d |
279 | return $viacode{$hex} if exists $viacode{$hex}; |
4e2cda5d |
280 | |
35c0985d |
281 | $txt = do "unicore/Name.pl" unless $txt; |
b177ca84 |
282 | |
bd5c3bd9 |
283 | return unless $txt =~ m/^$hex\t\t(.+)/m; |
284 | |
285 | $viacode{$hex} = $1; |
35c0985d |
286 | } # viacode |
daf0d493 |
287 | |
4e2cda5d |
288 | my %vianame; |
289 | |
daf0d493 |
290 | sub vianame |
291 | { |
35c0985d |
292 | if (@_ != 1) { |
293 | carp "charnames::vianame() expects one name argument"; |
294 | return () |
295 | } |
daf0d493 |
296 | |
35c0985d |
297 | my $arg = shift; |
daf0d493 |
298 | |
35c0985d |
299 | return chr hex $1 if $arg =~ /^U\+([0-9a-fA-F]+)$/; |
dbc0d4f2 |
300 | |
35c0985d |
301 | return $vianame{$arg} if exists $vianame{$arg}; |
4e2cda5d |
302 | |
35c0985d |
303 | $txt = do "unicore/Name.pl" unless $txt; |
daf0d493 |
304 | |
35c0985d |
305 | my $pos = index $txt, "\t\t$arg\n"; |
306 | if ($[ <= $pos) { |
307 | my $posLF = rindex $txt, "\n", $pos; |
308 | (my $code = substr $txt, $posLF + 1, 6) =~ tr/\t//d; |
309 | return $vianame{$arg} = hex $code; |
310 | |
311 | # If $pos is at the 1st line, $posLF must be $[ - 1 (not found); |
312 | # then $posLF + 1 equals to $[ (at the beginning of $txt). |
313 | # Otherwise $posLF is the position of "\n"; |
314 | # then $posLF + 1 must be the position of the next to "\n" |
315 | # (the beginning of the line). |
316 | # substr($txt, $posLF + 1, 6) may be "0000\t\t", "00A1\t\t", |
317 | # "10300\t", "100000", etc. So we can get the code via removing TAB. |
318 | } else { |
319 | return; |
320 | } |
321 | } # vianame |
b177ca84 |
322 | |
423cee85 |
323 | |
324 | 1; |
325 | __END__ |
326 | |
327 | =head1 NAME |
328 | |
274085e3 |
329 | charnames - define character names for C<\N{named}> string literal escapes |
423cee85 |
330 | |
331 | =head1 SYNOPSIS |
332 | |
333 | use charnames ':full'; |
4a2d328f |
334 | print "\N{GREEK SMALL LETTER SIGMA} is called sigma.\n"; |
423cee85 |
335 | |
336 | use charnames ':short'; |
4a2d328f |
337 | print "\N{greek:Sigma} is an upper-case sigma.\n"; |
423cee85 |
338 | |
339 | use charnames qw(cyrillic greek); |
4a2d328f |
340 | print "\N{sigma} is Greek sigma, and \N{be} is Cyrillic b.\n"; |
423cee85 |
341 | |
35c0985d |
342 | use charnames ":full", ":alias" => { |
343 | e_ACUTE => "LATIN SMALL LETTER E WITH ACUTE", |
76ae0c45 |
344 | }; |
35c0985d |
345 | print "\N{e_ACUTE} is a small letter e with an acute.\n"; |
346 | |
76ae0c45 |
347 | use charnames (); |
a23c04e4 |
348 | print charnames::viacode(0x1234); # prints "ETHIOPIC SYLLABLE SEE" |
349 | printf "%04X", charnames::vianame("GOTHIC LETTER AHSA"); # prints "10330" |
b177ca84 |
350 | |
423cee85 |
351 | =head1 DESCRIPTION |
352 | |
35c0985d |
353 | Pragma C<use charnames> supports arguments C<:full>, C<:short>, script |
354 | names and customized aliases. If C<:full> is present, for expansion of |
76ae0c45 |
355 | C<\N{CHARNAME}>, the string C<CHARNAME> is first looked up in the list of |
356 | standard Unicode character names. If C<:short> is present, and |
423cee85 |
357 | C<CHARNAME> has the form C<SCRIPT:CNAME>, then C<CNAME> is looked up |
358 | as a letter in script C<SCRIPT>. If pragma C<use charnames> is used |
a191c821 |
359 | with script name arguments, then for C<\N{CHARNAME}> the name |
423cee85 |
360 | C<CHARNAME> is looked up as a letter in the given scripts (in the |
35c0985d |
361 | specified order). Customized aliases are explained in L</CUSTOM ALIASES>. |
423cee85 |
362 | |
363 | For lookup of C<CHARNAME> inside a given script C<SCRIPTNAME> |
d5448623 |
364 | this pragma looks for the names |
423cee85 |
365 | |
366 | SCRIPTNAME CAPITAL LETTER CHARNAME |
367 | SCRIPTNAME SMALL LETTER CHARNAME |
368 | SCRIPTNAME LETTER CHARNAME |
369 | |
370 | in the table of standard Unicode names. If C<CHARNAME> is lowercase, |
daf0d493 |
371 | then the C<CAPITAL> variant is ignored, otherwise the C<SMALL> variant |
372 | is ignored. |
373 | |
374 | Note that C<\N{...}> is compile-time, it's a special form of string |
375 | constant used inside double-quoted strings: in other words, you cannot |
4e2cda5d |
376 | use variables inside the C<\N{...}>. If you want similar run-time |
daf0d493 |
377 | functionality, use charnames::vianame(). |
423cee85 |
378 | |
301a3cda |
379 | For the C0 and C1 control characters (U+0000..U+001F, U+0080..U+009F) |
dbc0d4f2 |
380 | as of Unicode 3.1, there are no official Unicode names but you can use |
381 | instead the ISO 6429 names (LINE FEED, ESCAPE, and so forth). In |
382 | Unicode 3.2 (as of Perl 5.8) some naming changes take place ISO 6429 |
383 | has been updated, see L</ALIASES>. Also note that the U+UU80, U+0081, |
384 | U+0084, and U+0099 do not have names even in ISO 6429. |
385 | |
386 | Since the Unicode standard uses "U+HHHH", so can you: "\N{U+263a}" |
387 | is the Unicode smiley face, or "\N{WHITE SMILING FACE}". |
301a3cda |
388 | |
423cee85 |
389 | =head1 CUSTOM TRANSLATORS |
390 | |
d5448623 |
391 | The mechanism of translation of C<\N{...}> escapes is general and not |
423cee85 |
392 | hardwired into F<charnames.pm>. A module can install custom |
d5448623 |
393 | translations (inside the scope which C<use>s the module) with the |
423cee85 |
394 | following magic incantation: |
395 | |
d5448623 |
396 | use charnames (); # for $charnames::hint_bits |
397 | sub import { |
398 | shift; |
399 | $^H |= $charnames::hint_bits; |
400 | $^H{charnames} = \&translator; |
401 | } |
423cee85 |
402 | |
403 | Here translator() is a subroutine which takes C<CHARNAME> as an |
404 | argument, and returns text to insert into the string instead of the |
4a2d328f |
405 | C<\N{CHARNAME}> escape. Since the text to insert should be different |
d5448623 |
406 | in C<bytes> mode and out of it, the function should check the current |
407 | state of C<bytes>-flag as in: |
408 | |
409 | use bytes (); # for $bytes::hint_bits |
410 | sub translator { |
411 | if ($^H & $bytes::hint_bits) { |
412 | return bytes_translator(@_); |
413 | } |
414 | else { |
415 | return utf8_translator(@_); |
416 | } |
423cee85 |
417 | } |
423cee85 |
418 | |
35c0985d |
419 | =head1 CUSTOM ALIASES |
420 | |
421 | This version of charnames supports three mechanisms of adding local |
422 | or customized aliases to standard Unicode naming conventions (:full) |
423 | |
424 | =head2 Anonymous hashes |
425 | |
426 | use charnames ":full", ":alias" => { |
427 | e_ACUTE => "LATIN SMALL LETTER E WITH ACUTE", |
428 | }; |
429 | my $str = "\N{e_ACUTE}"; |
430 | |
431 | =head2 Alias file |
432 | |
433 | use charnames ":full", ":alias" => "pro"; |
434 | |
435 | will try to read "unicore/pro_alias.pl" from the @INC path. This |
436 | file should return a list in plain perl: |
437 | |
438 | ( |
439 | A_GRAVE => "LATIN CAPITAL LETTER A WITH GRAVE", |
440 | A_CIRCUM => "LATIN CAPITAL LETTER A WITH CIRCUMFLEX", |
441 | A_DIAERES => "LATIN CAPITAL LETTER A WITH DIAERESIS", |
442 | A_TILDE => "LATIN CAPITAL LETTER A WITH TILDE", |
443 | A_BREVE => "LATIN CAPITAL LETTER A WITH BREVE", |
444 | A_RING => "LATIN CAPITAL LETTER A WITH RING ABOVE", |
445 | A_MACRON => "LATIN CAPITAL LETTER A WITH MACRON", |
446 | ); |
447 | |
448 | =head2 Alias shortcut |
449 | |
450 | use charnames ":alias" => ":pro"; |
451 | |
452 | works exactly the same as the alias pairs, only this time, |
453 | ":full" is inserted automatically as first argument (if no |
454 | other argument is given). |
455 | |
b177ca84 |
456 | =head1 charnames::viacode(code) |
457 | |
458 | Returns the full name of the character indicated by the numeric code. |
459 | The example |
460 | |
461 | print charnames::viacode(0x2722); |
462 | |
463 | prints "FOUR TEARDROP-SPOKED ASTERISK". |
464 | |
daf0d493 |
465 | Returns undef if no name is known for the code. |
466 | |
35c0985d |
467 | This works only for the standard names, and does not yet apply |
daf0d493 |
468 | to custom translators. |
469 | |
274085e3 |
470 | Notice that the name returned for of U+FEFF is "ZERO WIDTH NO-BREAK |
471 | SPACE", not "BYTE ORDER MARK". |
472 | |
eb6a2339 |
473 | =head1 charnames::vianame(name) |
daf0d493 |
474 | |
475 | Returns the code point indicated by the name. |
476 | The example |
477 | |
478 | printf "%04X", charnames::vianame("FOUR TEARDROP-SPOKED ASTERISK"); |
479 | |
480 | prints "2722". |
481 | |
eb6a2339 |
482 | Returns undef if the name is unknown. |
b177ca84 |
483 | |
35c0985d |
484 | This works only for the standard names, and does not yet apply |
b177ca84 |
485 | to custom translators. |
486 | |
52ea3e69 |
487 | =head1 ALIASES |
488 | |
489 | A few aliases have been defined for convenience: instead of having |
490 | to use the official names |
491 | |
492 | LINE FEED (LF) |
493 | FORM FEED (FF) |
494 | CARRIAGE RETURN (CR) |
495 | NEXT LINE (NEL) |
496 | |
497 | (yes, with parentheses) one can use |
498 | |
499 | LINE FEED |
500 | FORM FEED |
501 | CARRIAGE RETURN |
502 | NEXT LINE |
503 | LF |
504 | FF |
505 | CR |
506 | NEL |
507 | |
508 | One can also use |
509 | |
510 | BYTE ORDER MARK |
511 | BOM |
512 | |
24b5d5cc |
513 | and |
514 | |
515 | ZWNJ |
516 | ZWJ |
517 | |
518 | for ZERO WIDTH NON-JOINER and ZERO WIDTH JOINER. |
52ea3e69 |
519 | |
520 | For backward compatibility one can use the old names for |
521 | certain C0 and C1 controls |
522 | |
523 | old new |
524 | |
525 | HORIZONTAL TABULATION CHARACTER TABULATION |
526 | VERTICAL TABULATION LINE TABULATION |
527 | FILE SEPARATOR INFORMATION SEPARATOR FOUR |
528 | GROUP SEPARATOR INFORMATION SEPARATOR THREE |
529 | RECORD SEPARATOR INFORMATION SEPARATOR TWO |
530 | UNIT SEPARATOR INFORMATION SEPARATOR ONE |
531 | PARTIAL LINE DOWN PARTIAL LINE FORWARD |
532 | PARTIAL LINE UP PARTIAL LINE BACKWARD |
533 | |
534 | but the old names in addition to giving the character |
535 | will also give a warning about being deprecated. |
536 | |
f0175764 |
537 | =head1 ILLEGAL CHARACTERS |
538 | |
00d835f2 |
539 | If you ask by name for a character that does not exist, a warning is |
540 | given and the Unicode I<replacement character> "\x{FFFD}" is returned. |
541 | |
542 | If you ask by code for a character that does not exist, no warning is |
543 | given and C<undef> is returned. (Though if you ask for a code point |
544 | past U+10FFFF you do get a warning.) |
f0175764 |
545 | |
423cee85 |
546 | =head1 BUGS |
547 | |
548 | Since evaluation of the translation function happens in a middle of |
549 | compilation (of a string literal), the translation function should not |
550 | do any C<eval>s or C<require>s. This restriction should be lifted in |
551 | a future version of Perl. |
552 | |
553 | =cut |