| 1 |
package charnames; |
| 2 |
use strict; |
| 3 |
use warnings; |
| 4 |
use Carp; |
| 5 |
use File::Spec; |
| 6 |
our $VERSION = '1.04'; |
| 7 |
|
| 8 |
use bytes (); # for $bytes::hint_bits |
| 9 |
$charnames::hint_bits = 0x20000; # HINT_LOCALIZE_HH |
| 10 |
|
| 11 |
my %alias1 = ( |
| 12 |
# Icky 3.2 names with parentheses. |
| 13 |
'LINE FEED' => 'LINE FEED (LF)', |
| 14 |
'FORM FEED' => 'FORM FEED (FF)', |
| 15 |
'CARRIAGE RETURN' => 'CARRIAGE RETURN (CR)', |
| 16 |
'NEXT LINE' => 'NEXT LINE (NEL)', |
| 17 |
# Convenience. |
| 18 |
'LF' => 'LINE FEED (LF)', |
| 19 |
'FF' => 'FORM FEED (FF)', |
| 20 |
'CR' => 'CARRIAGE RETURN (CR)', |
| 21 |
'NEL' => 'NEXT LINE (NEL)', |
| 22 |
# More convenience. For futher convencience, |
| 23 |
# it is suggested some way using using the NamesList |
| 24 |
# aliases is implemented. |
| 25 |
'ZWNJ' => 'ZERO WIDTH NON-JOINER', |
| 26 |
'ZWJ' => 'ZERO WIDTH JOINER', |
| 27 |
'BOM' => 'BYTE ORDER MARK', |
| 28 |
); |
| 29 |
|
| 30 |
my %alias2 = ( |
| 31 |
# Pre-3.2 compatibility (only for the first 256 characters). |
| 32 |
'HORIZONTAL TABULATION' => 'CHARACTER TABULATION', |
| 33 |
'VERTICAL TABULATION' => 'LINE TABULATION', |
| 34 |
'FILE SEPARATOR' => 'INFORMATION SEPARATOR FOUR', |
| 35 |
'GROUP SEPARATOR' => 'INFORMATION SEPARATOR THREE', |
| 36 |
'RECORD SEPARATOR' => 'INFORMATION SEPARATOR TWO', |
| 37 |
'UNIT SEPARATOR' => 'INFORMATION SEPARATOR ONE', |
| 38 |
'PARTIAL LINE DOWN' => 'PARTIAL LINE FORWARD', |
| 39 |
'PARTIAL LINE UP' => 'PARTIAL LINE BACKWARD', |
| 40 |
); |
| 41 |
|
| 42 |
my %alias3 = ( |
| 43 |
# User defined aliasses. Even more convenient :) |
| 44 |
); |
| 45 |
my $txt; |
| 46 |
|
| 47 |
sub alias (@) |
| 48 |
{ |
| 49 |
@_ or return %alias3; |
| 50 |
my $alias = ref $_[0] ? $_[0] : { @_ }; |
| 51 |
@alias3{keys %$alias} = values %$alias; |
| 52 |
} # alias |
| 53 |
|
| 54 |
sub alias_file ($) |
| 55 |
{ |
| 56 |
my ($arg, $file) = @_; |
| 57 |
if (-f $arg && File::Spec->file_name_is_absolute ($arg)) { |
| 58 |
$file = $arg; |
| 59 |
} |
| 60 |
elsif ($arg =~ m/^\w+$/) { |
| 61 |
$file = "unicore/${arg}_alias.pl"; |
| 62 |
} |
| 63 |
else { |
| 64 |
croak "Charnames alias files can only have identifier characters"; |
| 65 |
} |
| 66 |
if (my @alias = do $file) { |
| 67 |
@alias == 1 && !defined $alias[0] and |
| 68 |
croak "$file cannot be used as alias file for charnames"; |
| 69 |
@alias % 2 and |
| 70 |
croak "$file did not return a (valid) list of alias pairs"; |
| 71 |
alias (@alias); |
| 72 |
return (1); |
| 73 |
} |
| 74 |
0; |
| 75 |
} # alias_file |
| 76 |
|
| 77 |
# This is not optimized in any way yet |
| 78 |
sub charnames |
| 79 |
{ |
| 80 |
my $name = shift; |
| 81 |
|
| 82 |
if (exists $alias1{$name}) { |
| 83 |
$name = $alias1{$name}; |
| 84 |
} |
| 85 |
elsif (exists $alias2{$name}) { |
| 86 |
require warnings; |
| 87 |
warnings::warnif('deprecated', qq{Unicode character name "$name" is deprecated, use "$alias2{$name}" instead}); |
| 88 |
$name = $alias2{$name}; |
| 89 |
} |
| 90 |
elsif (exists $alias3{$name}) { |
| 91 |
$name = $alias3{$name}; |
| 92 |
} |
| 93 |
|
| 94 |
my $ord; |
| 95 |
my @off; |
| 96 |
my $fname; |
| 97 |
|
| 98 |
if ($name eq "BYTE ORDER MARK") { |
| 99 |
$fname = $name; |
| 100 |
$ord = 0xFEFF; |
| 101 |
} else { |
| 102 |
## Suck in the code/name list as a big string. |
| 103 |
## Lines look like: |
| 104 |
## "0052\t\tLATIN CAPITAL LETTER R\n" |
| 105 |
$txt = do "unicore/Name.pl" unless $txt; |
| 106 |
|
| 107 |
## @off will hold the index into the code/name string of the start and |
| 108 |
## end of the name as we find it. |
| 109 |
|
| 110 |
## If :full, look for the name exactly |
| 111 |
if ($^H{charnames_full} and $txt =~ /\t\t\Q$name\E$/m) { |
| 112 |
@off = ($-[0], $+[0]); |
| 113 |
} |
| 114 |
|
| 115 |
## If we didn't get above, and :short allowed, look for the short name. |
| 116 |
## The short name is like "greek:Sigma" |
| 117 |
unless (@off) { |
| 118 |
if ($^H{charnames_short} and $name =~ /^(.+?):(.+)/s) { |
| 119 |
my ($script, $cname) = ($1, $2); |
| 120 |
my $case = $cname =~ /[[:upper:]]/ ? "CAPITAL" : "SMALL"; |
| 121 |
if ($txt =~ m/\t\t\U$script\E (?:$case )?LETTER \U\Q$cname\E$/m) { |
| 122 |
@off = ($-[0], $+[0]); |
| 123 |
} |
| 124 |
} |
| 125 |
} |
| 126 |
|
| 127 |
## If we still don't have it, check for the name among the loaded |
| 128 |
## scripts. |
| 129 |
if (not @off) { |
| 130 |
my $case = $name =~ /[[:upper:]]/ ? "CAPITAL" : "SMALL"; |
| 131 |
for my $script (@{$^H{charnames_scripts}}) { |
| 132 |
if ($txt =~ m/\t\t$script (?:$case )?LETTER \U\Q$name\E$/m) { |
| 133 |
@off = ($-[0], $+[0]); |
| 134 |
last; |
| 135 |
} |
| 136 |
} |
| 137 |
} |
| 138 |
|
| 139 |
## If we don't have it by now, give up. |
| 140 |
unless (@off) { |
| 141 |
carp "Unknown charname '$name'"; |
| 142 |
return "\x{FFFD}"; |
| 143 |
} |
| 144 |
|
| 145 |
## |
| 146 |
## Now know where in the string the name starts. |
| 147 |
## The code, in hex, is before that. |
| 148 |
## |
| 149 |
## The code can be 4-6 characters long, so we've got to sort of |
| 150 |
## go look for it, just after the newline that comes before $off[0]. |
| 151 |
## |
| 152 |
## This would be much easier if unicore/Name.pl had info in |
| 153 |
## a name/code order, instead of code/name order. |
| 154 |
## |
| 155 |
## The +1 after the rindex() is to skip past the newline we're finding, |
| 156 |
## or, if the rindex() fails, to put us to an offset of zero. |
| 157 |
## |
| 158 |
my $hexstart = rindex($txt, "\n", $off[0]) + 1; |
| 159 |
|
| 160 |
## we know where it starts, so turn into number - |
| 161 |
## the ordinal for the char. |
| 162 |
$ord = hex substr($txt, $hexstart, $off[0] - $hexstart); |
| 163 |
} |
| 164 |
|
| 165 |
if ($^H & $bytes::hint_bits) { # "use bytes" in effect? |
| 166 |
use bytes; |
| 167 |
return chr $ord if $ord <= 255; |
| 168 |
my $hex = sprintf "%04x", $ord; |
| 169 |
if (not defined $fname) { |
| 170 |
$fname = substr $txt, $off[0] + 2, $off[1] - $off[0] - 2; |
| 171 |
} |
| 172 |
croak "Character 0x$hex with name '$fname' is above 0xFF"; |
| 173 |
} |
| 174 |
|
| 175 |
no warnings 'utf8'; # allow even illegal characters |
| 176 |
return pack "U", $ord; |
| 177 |
} # charnames |
| 178 |
|
| 179 |
sub import |
| 180 |
{ |
| 181 |
shift; ## ignore class name |
| 182 |
|
| 183 |
if (not @_) { |
| 184 |
carp("`use charnames' needs explicit imports list"); |
| 185 |
} |
| 186 |
$^H |= $charnames::hint_bits; |
| 187 |
$^H{charnames} = \&charnames ; |
| 188 |
|
| 189 |
## |
| 190 |
## fill %h keys with our @_ args. |
| 191 |
## |
| 192 |
my ($promote, %h, @args) = (0); |
| 193 |
while (my $arg = shift) { |
| 194 |
if ($arg eq ":alias") { |
| 195 |
@_ or |
| 196 |
croak ":alias needs an argument in charnames"; |
| 197 |
my $alias = shift; |
| 198 |
if (ref $alias) { |
| 199 |
ref $alias eq "HASH" or |
| 200 |
croak "Only HASH reference supported as argument to :alias"; |
| 201 |
alias ($alias); |
| 202 |
next; |
| 203 |
} |
| 204 |
if ($alias =~ m{:(\w+)$}) { |
| 205 |
$1 eq "full" || $1 eq "short" and |
| 206 |
croak ":alias cannot use existing pragma :$1 (reversed order?)"; |
| 207 |
alias_file ($1) and $promote = 1; |
| 208 |
next; |
| 209 |
} |
| 210 |
alias_file ($alias); |
| 211 |
next; |
| 212 |
} |
| 213 |
if (substr($arg, 0, 1) eq ':' and ! ($arg eq ":full" || $arg eq ":short")) { |
| 214 |
warn "unsupported special '$arg' in charnames"; |
| 215 |
next; |
| 216 |
} |
| 217 |
push @args, $arg; |
| 218 |
} |
| 219 |
@args == 0 && $promote and @args = (":full"); |
| 220 |
@h{@args} = (1) x @args; |
| 221 |
|
| 222 |
$^H{charnames_full} = delete $h{':full'}; |
| 223 |
$^H{charnames_short} = delete $h{':short'}; |
| 224 |
$^H{charnames_scripts} = [map uc, keys %h]; |
| 225 |
|
| 226 |
## |
| 227 |
## If utf8? warnings are enabled, and some scripts were given, |
| 228 |
## see if at least we can find one letter of each script. |
| 229 |
## |
| 230 |
if (warnings::enabled('utf8') && @{$^H{charnames_scripts}}) { |
| 231 |
$txt = do "unicore/Name.pl" unless $txt; |
| 232 |
|
| 233 |
for my $script (@{$^H{charnames_scripts}}) { |
| 234 |
if (not $txt =~ m/\t\t$script (?:CAPITAL |SMALL )?LETTER /) { |
| 235 |
warnings::warn('utf8', "No such script: '$script'"); |
| 236 |
} |
| 237 |
} |
| 238 |
} |
| 239 |
} # import |
| 240 |
|
| 241 |
# this comes actually from Unicode::UCD, but it avoids the |
| 242 |
# overhead of loading it |
| 243 |
sub _getcode { |
| 244 |
my $arg = shift; |
| 245 |
|
| 246 |
if ($arg =~ /^[1-9]\d*$/) { |
| 247 |
return $arg; |
| 248 |
} elsif ($arg =~ /^(?:[Uu]\+|0[xX])?([[:xdigit:]]+)$/) { |
| 249 |
return hex($1); |
| 250 |
} |
| 251 |
|
| 252 |
return; |
| 253 |
} |
| 254 |
|
| 255 |
my %viacode; |
| 256 |
|
| 257 |
sub viacode |
| 258 |
{ |
| 259 |
if (@_ != 1) { |
| 260 |
carp "charnames::viacode() expects one argument"; |
| 261 |
return () |
| 262 |
} |
| 263 |
|
| 264 |
my $arg = shift; |
| 265 |
my $code = _getcode($arg); |
| 266 |
|
| 267 |
my $hex; |
| 268 |
|
| 269 |
if (defined $code) { |
| 270 |
$hex = sprintf "%04X", $arg; |
| 271 |
} else { |
| 272 |
carp("unexpected arg \"$arg\" to charnames::viacode()"); |
| 273 |
return; |
| 274 |
} |
| 275 |
|
| 276 |
if ($code > 0x10FFFF) { |
| 277 |
carp sprintf "Unicode characters only allocated up to U+10FFFF (you asked for U+%X)", $hex; |
| 278 |
return; |
| 279 |
} |
| 280 |
|
| 281 |
return $viacode{$hex} if exists $viacode{$hex}; |
| 282 |
|
| 283 |
$txt = do "unicore/Name.pl" unless $txt; |
| 284 |
|
| 285 |
if ($txt =~ m/^$hex\t\t(.+)/m) { |
| 286 |
return $viacode{$hex} = $1; |
| 287 |
} else { |
| 288 |
return; |
| 289 |
} |
| 290 |
} # viacode |
| 291 |
|
| 292 |
my %vianame; |
| 293 |
|
| 294 |
sub vianame |
| 295 |
{ |
| 296 |
if (@_ != 1) { |
| 297 |
carp "charnames::vianame() expects one name argument"; |
| 298 |
return () |
| 299 |
} |
| 300 |
|
| 301 |
my $arg = shift; |
| 302 |
|
| 303 |
return chr hex $1 if $arg =~ /^U\+([0-9a-fA-F]+)$/; |
| 304 |
|
| 305 |
return $vianame{$arg} if exists $vianame{$arg}; |
| 306 |
|
| 307 |
$txt = do "unicore/Name.pl" unless $txt; |
| 308 |
|
| 309 |
my $pos = index $txt, "\t\t$arg\n"; |
| 310 |
if ($[ <= $pos) { |
| 311 |
my $posLF = rindex $txt, "\n", $pos; |
| 312 |
(my $code = substr $txt, $posLF + 1, 6) =~ tr/\t//d; |
| 313 |
return $vianame{$arg} = hex $code; |
| 314 |
|
| 315 |
# If $pos is at the 1st line, $posLF must be $[ - 1 (not found); |
| 316 |
# then $posLF + 1 equals to $[ (at the beginning of $txt). |
| 317 |
# Otherwise $posLF is the position of "\n"; |
| 318 |
# then $posLF + 1 must be the position of the next to "\n" |
| 319 |
# (the beginning of the line). |
| 320 |
# substr($txt, $posLF + 1, 6) may be "0000\t\t", "00A1\t\t", |
| 321 |
# "10300\t", "100000", etc. So we can get the code via removing TAB. |
| 322 |
} else { |
| 323 |
return; |
| 324 |
} |
| 325 |
} # vianame |
| 326 |
|
| 327 |
|
| 328 |
1; |
| 329 |
__END__ |
| 330 |
|
| 331 |
=head1 NAME |
| 332 |
|
| 333 |
charnames - define character names for C<\N{named}> string literal escapes |
| 334 |
|
| 335 |
=head1 SYNOPSIS |
| 336 |
|
| 337 |
use charnames ':full'; |
| 338 |
print "\N{GREEK SMALL LETTER SIGMA} is called sigma.\n"; |
| 339 |
|
| 340 |
use charnames ':short'; |
| 341 |
print "\N{greek:Sigma} is an upper-case sigma.\n"; |
| 342 |
|
| 343 |
use charnames qw(cyrillic greek); |
| 344 |
print "\N{sigma} is Greek sigma, and \N{be} is Cyrillic b.\n"; |
| 345 |
|
| 346 |
use charnames ":full", ":alias" => { |
| 347 |
e_ACUTE => "LATIN SMALL LETTER E WITH ACUTE", |
| 348 |
}; |
| 349 |
print "\N{e_ACUTE} is a small letter e with an acute.\n"; |
| 350 |
|
| 351 |
use charnames (); |
| 352 |
print charnames::viacode(0x1234); # prints "ETHIOPIC SYLLABLE SEE" |
| 353 |
printf "%04X", charnames::vianame("GOTHIC LETTER AHSA"); # prints "10330" |
| 354 |
|
| 355 |
=head1 DESCRIPTION |
| 356 |
|
| 357 |
Pragma C<use charnames> supports arguments C<:full>, C<:short>, script |
| 358 |
names and customized aliases. If C<:full> is present, for expansion of |
| 359 |
C<\N{CHARNAME}>, the string C<CHARNAME> is first looked up in the list of |
| 360 |
standard Unicode character names. If C<:short> is present, and |
| 361 |
C<CHARNAME> has the form C<SCRIPT:CNAME>, then C<CNAME> is looked up |
| 362 |
as a letter in script C<SCRIPT>. If pragma C<use charnames> is used |
| 363 |
with script name arguments, then for C<\N{CHARNAME}> the name |
| 364 |
C<CHARNAME> is looked up as a letter in the given scripts (in the |
| 365 |
specified order). Customized aliases are explained in L</CUSTOM ALIASES>. |
| 366 |
|
| 367 |
For lookup of C<CHARNAME> inside a given script C<SCRIPTNAME> |
| 368 |
this pragma looks for the names |
| 369 |
|
| 370 |
SCRIPTNAME CAPITAL LETTER CHARNAME |
| 371 |
SCRIPTNAME SMALL LETTER CHARNAME |
| 372 |
SCRIPTNAME LETTER CHARNAME |
| 373 |
|
| 374 |
in the table of standard Unicode names. If C<CHARNAME> is lowercase, |
| 375 |
then the C<CAPITAL> variant is ignored, otherwise the C<SMALL> variant |
| 376 |
is ignored. |
| 377 |
|
| 378 |
Note that C<\N{...}> is compile-time, it's a special form of string |
| 379 |
constant used inside double-quoted strings: in other words, you cannot |
| 380 |
use variables inside the C<\N{...}>. If you want similar run-time |
| 381 |
functionality, use charnames::vianame(). |
| 382 |
|
| 383 |
For the C0 and C1 control characters (U+0000..U+001F, U+0080..U+009F) |
| 384 |
as of Unicode 3.1, there are no official Unicode names but you can use |
| 385 |
instead the ISO 6429 names (LINE FEED, ESCAPE, and so forth). In |
| 386 |
Unicode 3.2 (as of Perl 5.8) some naming changes take place ISO 6429 |
| 387 |
has been updated, see L</ALIASES>. Also note that the U+UU80, U+0081, |
| 388 |
U+0084, and U+0099 do not have names even in ISO 6429. |
| 389 |
|
| 390 |
Since the Unicode standard uses "U+HHHH", so can you: "\N{U+263a}" |
| 391 |
is the Unicode smiley face, or "\N{WHITE SMILING FACE}". |
| 392 |
|
| 393 |
=head1 CUSTOM TRANSLATORS |
| 394 |
|
| 395 |
The mechanism of translation of C<\N{...}> escapes is general and not |
| 396 |
hardwired into F<charnames.pm>. A module can install custom |
| 397 |
translations (inside the scope which C<use>s the module) with the |
| 398 |
following magic incantation: |
| 399 |
|
| 400 |
use charnames (); # for $charnames::hint_bits |
| 401 |
sub import { |
| 402 |
shift; |
| 403 |
$^H |= $charnames::hint_bits; |
| 404 |
$^H{charnames} = \&translator; |
| 405 |
} |
| 406 |
|
| 407 |
Here translator() is a subroutine which takes C<CHARNAME> as an |
| 408 |
argument, and returns text to insert into the string instead of the |
| 409 |
C<\N{CHARNAME}> escape. Since the text to insert should be different |
| 410 |
in C<bytes> mode and out of it, the function should check the current |
| 411 |
state of C<bytes>-flag as in: |
| 412 |
|
| 413 |
use bytes (); # for $bytes::hint_bits |
| 414 |
sub translator { |
| 415 |
if ($^H & $bytes::hint_bits) { |
| 416 |
return bytes_translator(@_); |
| 417 |
} |
| 418 |
else { |
| 419 |
return utf8_translator(@_); |
| 420 |
} |
| 421 |
} |
| 422 |
|
| 423 |
=head1 CUSTOM ALIASES |
| 424 |
|
| 425 |
This version of charnames supports three mechanisms of adding local |
| 426 |
or customized aliases to standard Unicode naming conventions (:full) |
| 427 |
|
| 428 |
=head2 Anonymous hashes |
| 429 |
|
| 430 |
use charnames ":full", ":alias" => { |
| 431 |
e_ACUTE => "LATIN SMALL LETTER E WITH ACUTE", |
| 432 |
}; |
| 433 |
my $str = "\N{e_ACUTE}"; |
| 434 |
|
| 435 |
=head2 Alias file |
| 436 |
|
| 437 |
use charnames ":full", ":alias" => "pro"; |
| 438 |
|
| 439 |
will try to read "unicore/pro_alias.pl" from the @INC path. This |
| 440 |
file should return a list in plain perl: |
| 441 |
|
| 442 |
( |
| 443 |
A_GRAVE => "LATIN CAPITAL LETTER A WITH GRAVE", |
| 444 |
A_CIRCUM => "LATIN CAPITAL LETTER A WITH CIRCUMFLEX", |
| 445 |
A_DIAERES => "LATIN CAPITAL LETTER A WITH DIAERESIS", |
| 446 |
A_TILDE => "LATIN CAPITAL LETTER A WITH TILDE", |
| 447 |
A_BREVE => "LATIN CAPITAL LETTER A WITH BREVE", |
| 448 |
A_RING => "LATIN CAPITAL LETTER A WITH RING ABOVE", |
| 449 |
A_MACRON => "LATIN CAPITAL LETTER A WITH MACRON", |
| 450 |
); |
| 451 |
|
| 452 |
=head2 Alias shortcut |
| 453 |
|
| 454 |
use charnames ":alias" => ":pro"; |
| 455 |
|
| 456 |
works exactly the same as the alias pairs, only this time, |
| 457 |
":full" is inserted automatically as first argument (if no |
| 458 |
other argument is given). |
| 459 |
|
| 460 |
=head1 charnames::viacode(code) |
| 461 |
|
| 462 |
Returns the full name of the character indicated by the numeric code. |
| 463 |
The example |
| 464 |
|
| 465 |
print charnames::viacode(0x2722); |
| 466 |
|
| 467 |
prints "FOUR TEARDROP-SPOKED ASTERISK". |
| 468 |
|
| 469 |
Returns undef if no name is known for the code. |
| 470 |
|
| 471 |
This works only for the standard names, and does not yet apply |
| 472 |
to custom translators. |
| 473 |
|
| 474 |
Notice that the name returned for of U+FEFF is "ZERO WIDTH NO-BREAK |
| 475 |
SPACE", not "BYTE ORDER MARK". |
| 476 |
|
| 477 |
=head1 charnames::vianame(name) |
| 478 |
|
| 479 |
Returns the code point indicated by the name. |
| 480 |
The example |
| 481 |
|
| 482 |
printf "%04X", charnames::vianame("FOUR TEARDROP-SPOKED ASTERISK"); |
| 483 |
|
| 484 |
prints "2722". |
| 485 |
|
| 486 |
Returns undef if the name is unknown. |
| 487 |
|
| 488 |
This works only for the standard names, and does not yet apply |
| 489 |
to custom translators. |
| 490 |
|
| 491 |
=head1 ALIASES |
| 492 |
|
| 493 |
A few aliases have been defined for convenience: instead of having |
| 494 |
to use the official names |
| 495 |
|
| 496 |
LINE FEED (LF) |
| 497 |
FORM FEED (FF) |
| 498 |
CARRIAGE RETURN (CR) |
| 499 |
NEXT LINE (NEL) |
| 500 |
|
| 501 |
(yes, with parentheses) one can use |
| 502 |
|
| 503 |
LINE FEED |
| 504 |
FORM FEED |
| 505 |
CARRIAGE RETURN |
| 506 |
NEXT LINE |
| 507 |
LF |
| 508 |
FF |
| 509 |
CR |
| 510 |
NEL |
| 511 |
|
| 512 |
One can also use |
| 513 |
|
| 514 |
BYTE ORDER MARK |
| 515 |
BOM |
| 516 |
|
| 517 |
and |
| 518 |
|
| 519 |
ZWNJ |
| 520 |
ZWJ |
| 521 |
|
| 522 |
for ZERO WIDTH NON-JOINER and ZERO WIDTH JOINER. |
| 523 |
|
| 524 |
For backward compatibility one can use the old names for |
| 525 |
certain C0 and C1 controls |
| 526 |
|
| 527 |
old new |
| 528 |
|
| 529 |
HORIZONTAL TABULATION CHARACTER TABULATION |
| 530 |
VERTICAL TABULATION LINE TABULATION |
| 531 |
FILE SEPARATOR INFORMATION SEPARATOR FOUR |
| 532 |
GROUP SEPARATOR INFORMATION SEPARATOR THREE |
| 533 |
RECORD SEPARATOR INFORMATION SEPARATOR TWO |
| 534 |
UNIT SEPARATOR INFORMATION SEPARATOR ONE |
| 535 |
PARTIAL LINE DOWN PARTIAL LINE FORWARD |
| 536 |
PARTIAL LINE UP PARTIAL LINE BACKWARD |
| 537 |
|
| 538 |
but the old names in addition to giving the character |
| 539 |
will also give a warning about being deprecated. |
| 540 |
|
| 541 |
=head1 ILLEGAL CHARACTERS |
| 542 |
|
| 543 |
If you ask by name for a character that does not exist, a warning is |
| 544 |
given and the Unicode I<replacement character> "\x{FFFD}" is returned. |
| 545 |
|
| 546 |
If you ask by code for a character that does not exist, no warning is |
| 547 |
given and C<undef> is returned. (Though if you ask for a code point |
| 548 |
past U+10FFFF you do get a warning.) |
| 549 |
|
| 550 |
=head1 BUGS |
| 551 |
|
| 552 |
Since evaluation of the translation function happens in a middle of |
| 553 |
compilation (of a string literal), the translation function should not |
| 554 |
do any C<eval>s or C<require>s. This restriction should be lifted in |
| 555 |
a future version of Perl. |
| 556 |
|
| 557 |
=cut |
