| File | /usr/local/lib/perl/5.10.0/Encode/Alias.pm |
| Statements Executed | 380 |
| Total Time | 0.0028801 seconds |
| Calls | P | F | Exclusive Time |
Inclusive Time |
Subroutine |
|---|---|---|---|---|---|
| 44 | 44 | 1 | 623µs | 623µs | Encode::Alias::define_alias |
| 1 | 1 | 1 | 175µs | 806µs | Encode::Alias::init_aliases |
| 1 | 1 | 1 | 8µs | 8µs | Encode::Alias::undef_aliases |
| 0 | 0 | 0 | 0s | 0s | Encode::Alias::BEGIN |
| 0 | 0 | 0 | 0s | 0s | Encode::Alias::find_alias |
| Line | Stmts. | Exclusive Time | Avg. | Code |
|---|---|---|---|---|
| 1 | package Encode::Alias; | |||
| 2 | 3 | 26µs | 9µs | use strict; # spent 9µs making 1 call to strict::import |
| 3 | 3 | 33µs | 11µs | use warnings; # spent 22µs making 1 call to warnings::import |
| 4 | 3 | 83µs | 28µs | no warnings 'redefine'; # spent 20µs making 1 call to warnings::unimport |
| 5 | 3 | 19µs | 6µs | our $VERSION = do { my @r = ( q$Revision: 2.12 $ =~ /\d+/g ); sprintf "%d." . "%02d" x $#r, @r }; |
| 6 | sub DEBUG () { 0 } | |||
| 7 | ||||
| 8 | 3 | 1.87ms | 624µs | use base qw(Exporter); # spent 66µs making 1 call to base::import |
| 9 | ||||
| 10 | # Public, encouraged API is exported by default | |||
| 11 | ||||
| 12 | 1 | 1µs | 1µs | our @EXPORT = |
| 13 | qw ( | |||
| 14 | define_alias | |||
| 15 | find_alias | |||
| 16 | ); | |||
| 17 | ||||
| 18 | 1 | 400ns | 400ns | our @Alias; # ordered matching list |
| 19 | 1 | 300ns | 300ns | our %Alias; # cached known aliases |
| 20 | ||||
| 21 | sub find_alias { | |||
| 22 | require Encode; | |||
| 23 | my $class = shift; | |||
| 24 | my $find = shift; | |||
| 25 | unless ( exists $Alias{$find} ) { | |||
| 26 | $Alias{$find} = undef; # Recursion guard | |||
| 27 | for ( my $i = 0 ; $i < @Alias ; $i += 2 ) { | |||
| 28 | my $alias = $Alias[$i]; | |||
| 29 | my $val = $Alias[ $i + 1 ]; | |||
| 30 | my $new; | |||
| 31 | if ( ref($alias) eq 'Regexp' && $find =~ $alias ) { | |||
| 32 | DEBUG and warn "eval $val"; | |||
| 33 | $new = eval $val; | |||
| 34 | DEBUG and $@ and warn "$val, $@"; | |||
| 35 | } | |||
| 36 | elsif ( ref($alias) eq 'CODE' ) { | |||
| 37 | DEBUG and warn "$alias", "->", "($find)"; | |||
| 38 | $new = $alias->($find); | |||
| 39 | } | |||
| 40 | elsif ( lc($find) eq lc($alias) ) { | |||
| 41 | $new = $val; | |||
| 42 | } | |||
| 43 | if ( defined($new) ) { | |||
| 44 | next if $new eq $find; # avoid (direct) recursion on bugs | |||
| 45 | DEBUG and warn "$alias, $new"; | |||
| 46 | my $enc = | |||
| 47 | ( ref($new) ) ? $new : Encode::find_encoding($new); | |||
| 48 | if ($enc) { | |||
| 49 | $Alias{$find} = $enc; | |||
| 50 | last; | |||
| 51 | } | |||
| 52 | } | |||
| 53 | } | |||
| 54 | ||||
| 55 | # case insensitive search when canonical is not in all lowercase | |||
| 56 | # RT ticket #7835 | |||
| 57 | unless ( $Alias{$find} ) { | |||
| 58 | my $lcfind = lc($find); | |||
| 59 | for my $name ( keys %Encode::Encoding, keys %Encode::ExtModule ) | |||
| 60 | { | |||
| 61 | $lcfind eq lc($name) or next; | |||
| 62 | $Alias{$find} = Encode::find_encoding($name); | |||
| 63 | DEBUG and warn "$find => $name"; | |||
| 64 | } | |||
| 65 | } | |||
| 66 | } | |||
| 67 | if (DEBUG) { | |||
| 68 | my $name; | |||
| 69 | if ( my $e = $Alias{$find} ) { | |||
| 70 | $name = $e->name; | |||
| 71 | } | |||
| 72 | else { | |||
| 73 | $name = ""; | |||
| 74 | } | |||
| 75 | warn "find_alias($class, $find)->name = $name"; | |||
| 76 | } | |||
| 77 | return $Alias{$find}; | |||
| 78 | } | |||
| 79 | ||||
| 80 | # spent 623µs within Encode::Alias::define_alias which was called 44 times, avg 14µs/call:
# once (51µs+0s) by Encode::Alias::init_aliases at line 186
# once (29µs+0s) by Encode::Alias::init_aliases at line 145
# once (26µs+0s) by Encode::Alias::init_aliases at line 140
# once (17µs+0s) by Encode::Alias::init_aliases at line 239
# once (17µs+0s) by Encode::Alias::init_aliases at line 253
# once (17µs+0s) by Encode::Alias::init_aliases at line 243
# once (17µs+0s) by Encode::Alias::init_aliases at line 153
# once (17µs+0s) by Encode::Alias::init_aliases at line 222
# once (16µs+0s) by Encode::Alias::init_aliases at line 200
# once (16µs+0s) by Encode::Alias::init_aliases at line 135
# once (16µs+0s) by Encode::Alias::init_aliases at line 246
# once (15µs+0s) by Encode::Alias::init_aliases at line 138
# once (15µs+0s) by Encode::Alias::init_aliases at line 175
# once (14µs+0s) by Encode::Alias::init_aliases at line 179
# once (14µs+0s) by Encode::Alias::init_aliases at line 259
# once (14µs+0s) by Encode::Alias::init_aliases at line 248
# once (14µs+0s) by Encode::Alias::init_aliases at line 217
# once (13µs+0s) by Encode::Alias::init_aliases at line 154
# once (13µs+0s) by Encode::Alias::init_aliases at line 173
# once (13µs+0s) by Encode::Alias::init_aliases at line 233
# once (13µs+0s) by Encode::Alias::init_aliases at line 254
# once (13µs+0s) by Encode::Alias::init_aliases at line 262
# once (13µs+0s) by Encode::Alias::init_aliases at line 227
# once (13µs+0s) by Encode::Alias::init_aliases at line 255
# once (13µs+0s) by Encode::Alias::init_aliases at line 223
# once (13µs+0s) by Encode::Alias::init_aliases at line 235
# once (13µs+0s) by Encode::Alias::init_aliases at line 237
# once (13µs+0s) by Encode::Alias::init_aliases at line 251
# once (12µs+0s) by Encode::Alias::init_aliases at line 247
# once (12µs+0s) by Encode::Alias::init_aliases at line 209
# once (11µs+0s) by Encode::Alias::init_aliases at line 211
# once (11µs+0s) by Encode::Alias::init_aliases at line 168
# once (11µs+0s) by Encode::Alias::init_aliases at line 236
# once (10µs+0s) by Encode::Alias::init_aliases at line 157
# once (10µs+0s) by Encode::Alias::init_aliases at line 160
# once (10µs+0s) by Encode::Alias::init_aliases at line 139
# once (9µs+0s) by Encode::Alias::init_aliases at line 152
# once (9µs+0s) by Encode::Alias::init_aliases at line 242
# once (9µs+0s) by Encode::Alias::init_aliases at line 252
# once (9µs+0s) by Encode::Alias::init_aliases at line 195
# once (8µs+0s) by Encode::Alias::init_aliases at line 230
# once (8µs+0s) by Encode::Alias::init_aliases at line 234
# once (8µs+0s) by Encode::Alias::init_aliases at line 163
# once (8µs+0s) by Encode::Alias::init_aliases at line 238 | |||
| 81 | 309 | 352µs | 1µs | while (@_) { |
| 82 | my ( $alias, $name ) = splice( @_, 0, 2 ); | |||
| 83 | unshift( @Alias, $alias => $name ); # newer one has precedence | |||
| 84 | if ( ref($alias) ) { | |||
| 85 | ||||
| 86 | # clear %Alias cache to allow overrides | |||
| 87 | my @a = keys %Alias; | |||
| 88 | for my $k (@a) { | |||
| 89 | if ( ref($alias) eq 'Regexp' && $k =~ $alias ) { | |||
| 90 | DEBUG and warn "delete \$Alias\{$k\}"; | |||
| 91 | delete $Alias{$k}; | |||
| 92 | } | |||
| 93 | elsif ( ref($alias) eq 'CODE' ) { | |||
| 94 | DEBUG and warn "delete \$Alias\{$k\}"; | |||
| 95 | delete $Alias{ $alias->($name) }; | |||
| 96 | } | |||
| 97 | } | |||
| 98 | } | |||
| 99 | else { | |||
| 100 | DEBUG and warn "delete \$Alias\{$alias\}"; | |||
| 101 | delete $Alias{$alias}; | |||
| 102 | } | |||
| 103 | } | |||
| 104 | } | |||
| 105 | ||||
| 106 | # Allow latin-1 style names as well | |||
| 107 | # 0 1 2 3 4 5 6 7 8 9 10 | |||
| 108 | 1 | 2µs | 2µs | our @Latin2iso = ( 0, 1, 2, 3, 4, 9, 10, 13, 14, 15, 16 ); |
| 109 | ||||
| 110 | # Allow winlatin1 style names as well | |||
| 111 | 1 | 13µs | 13µs | our %Winlatin2cp = ( |
| 112 | 'latin1' => 1252, | |||
| 113 | 'latin2' => 1250, | |||
| 114 | 'cyrillic' => 1251, | |||
| 115 | 'greek' => 1253, | |||
| 116 | 'turkish' => 1254, | |||
| 117 | 'hebrew' => 1255, | |||
| 118 | 'arabic' => 1256, | |||
| 119 | 'baltic' => 1257, | |||
| 120 | 'vietnamese' => 1258, | |||
| 121 | ); | |||
| 122 | ||||
| 123 | 1 | 9µs | 9µs | init_aliases(); # spent 806µs making 1 call to Encode::Alias::init_aliases |
| 124 | ||||
| 125 | # spent 8µs within Encode::Alias::undef_aliases which was called
# once (8µs+0s) by Encode::Alias::init_aliases at line 132 | |||
| 126 | 2 | 2µs | 1µs | @Alias = (); |
| 127 | %Alias = (); | |||
| 128 | } | |||
| 129 | ||||
| 130 | # spent 806µs (175+631) within Encode::Alias::init_aliases which was called
# once (175µs+631µs) at line 123 | |||
| 131 | 47 | 444µs | 9µs | require Encode; |
| 132 | undef_aliases(); # spent 8µs making 1 call to Encode::Alias::undef_aliases | |||
| 133 | ||||
| 134 | # Try all-lower-case version should all else fails | |||
| 135 | define_alias( qr/^(.*)$/ => '"\L$1"' ); # spent 16µs making 1 call to Encode::Alias::define_alias | |||
| 136 | ||||
| 137 | # UTF/UCS stuff | |||
| 138 | define_alias( qr/^(unicode-1-1-)?UTF-?7$/i => '"UTF-7"' ); # spent 15µs making 1 call to Encode::Alias::define_alias | |||
| 139 | define_alias( qr/^UCS-?2-?LE$/i => '"UCS-2LE"' ); # spent 10µs making 1 call to Encode::Alias::define_alias | |||
| 140 | define_alias( # spent 26µs making 1 call to Encode::Alias::define_alias | |||
| 141 | qr/^UCS-?2-?(BE)?$/i => '"UCS-2BE"', | |||
| 142 | qr/^UCS-?4-?(BE|LE)?$/i => 'uc("UTF-32$1")', | |||
| 143 | qr/^iso-10646-1$/i => '"UCS-2BE"' | |||
| 144 | ); | |||
| 145 | define_alias( # spent 29µs making 1 call to Encode::Alias::define_alias | |||
| 146 | qr/^UTF-?(16|32)-?BE$/i => '"UTF-$1BE"', | |||
| 147 | qr/^UTF-?(16|32)-?LE$/i => '"UTF-$1LE"', | |||
| 148 | qr/^UTF-?(16|32)$/i => '"UTF-$1"', | |||
| 149 | ); | |||
| 150 | ||||
| 151 | # ASCII | |||
| 152 | define_alias( qr/^(?:US-?)ascii$/i => '"ascii"' ); # spent 9µs making 1 call to Encode::Alias::define_alias | |||
| 153 | define_alias( 'C' => 'ascii' ); # spent 17µs making 1 call to Encode::Alias::define_alias | |||
| 154 | define_alias( qr/\b(?:ISO[-_]?)?646(?:[-_]?US)?$/i => '"ascii"' ); # spent 13µs making 1 call to Encode::Alias::define_alias | |||
| 155 | ||||
| 156 | # Allow variants of iso-8859-1 etc. | |||
| 157 | define_alias( qr/\biso[-_]?(\d+)[-_](\d+)$/i => '"iso-$1-$2"' ); # spent 10µs making 1 call to Encode::Alias::define_alias | |||
| 158 | ||||
| 159 | # At least HP-UX has these. | |||
| 160 | define_alias( qr/\biso8859(\d+)$/i => '"iso-8859-$1"' ); # spent 10µs making 1 call to Encode::Alias::define_alias | |||
| 161 | ||||
| 162 | # More HP stuff. | |||
| 163 | define_alias( # spent 8µs making 1 call to Encode::Alias::define_alias | |||
| 164 | qr/\b(?:hp-)?(arabic|greek|hebrew|kana|roman|thai|turkish)8$/i => | |||
| 165 | '"${1}8"' ); | |||
| 166 | ||||
| 167 | # The Official name of ASCII. | |||
| 168 | define_alias( qr/\bANSI[-_]?X3\.4[-_]?1968$/i => '"ascii"' ); # spent 11µs making 1 call to Encode::Alias::define_alias | |||
| 169 | ||||
| 170 | # This is a font issue, not an encoding issue. | |||
| 171 | # (The currency symbol of the Latin 1 upper half | |||
| 172 | # has been redefined as the euro symbol.) | |||
| 173 | define_alias( qr/^(.+)\@euro$/i => '"$1"' ); # spent 13µs making 1 call to Encode::Alias::define_alias | |||
| 174 | ||||
| 175 | define_alias( qr/\b(?:iso[-_]?)?latin[-_]?(\d+)$/i => # spent 15µs making 1 call to Encode::Alias::define_alias | |||
| 176 | 'defined $Encode::Alias::Latin2iso[$1] ? "iso-8859-$Encode::Alias::Latin2iso[$1]" : undef' | |||
| 177 | ); | |||
| 178 | ||||
| 179 | define_alias( # spent 14µs making 1 call to Encode::Alias::define_alias | |||
| 180 | qr/\bwin(latin[12]|cyrillic|baltic|greek|turkish| | |||
| 181 | hebrew|arabic|baltic|vietnamese)$/ix => | |||
| 182 | '"cp" . $Encode::Alias::Winlatin2cp{lc($1)}' | |||
| 183 | ); | |||
| 184 | ||||
| 185 | # Common names for non-latin preferred MIME names | |||
| 186 | define_alias( # spent 51µs making 1 call to Encode::Alias::define_alias | |||
| 187 | 'ascii' => 'US-ascii', | |||
| 188 | 'cyrillic' => 'iso-8859-5', | |||
| 189 | 'arabic' => 'iso-8859-6', | |||
| 190 | 'greek' => 'iso-8859-7', | |||
| 191 | 'hebrew' => 'iso-8859-8', | |||
| 192 | 'thai' => 'iso-8859-11', | |||
| 193 | ); | |||
| 194 | # RT #20781 | |||
| 195 | define_alias(qr/\btis-?620\b/i => '"iso-8859-11"'); # spent 9µs making 1 call to Encode::Alias::define_alias | |||
| 196 | ||||
| 197 | # At least AIX has IBM-NNN (surprisingly...) instead of cpNNN. | |||
| 198 | # And Microsoft has their own naming (again, surprisingly). | |||
| 199 | # And windows-* is registered in IANA! | |||
| 200 | define_alias( # spent 16µs making 1 call to Encode::Alias::define_alias | |||
| 201 | qr/\b(?:cp|ibm|ms|windows)[-_ ]?(\d{2,4})$/i => '"cp$1"' ); | |||
| 202 | ||||
| 203 | # Sometimes seen with a leading zero. | |||
| 204 | # define_alias( qr/\bcp037\b/i => '"cp37"'); | |||
| 205 | ||||
| 206 | # Mac Mappings | |||
| 207 | # predefined in *.ucm; unneeded | |||
| 208 | # define_alias( qr/\bmacIcelandic$/i => '"macIceland"'); | |||
| 209 | define_alias( qr/^mac_(.*)$/i => '"mac$1"' ); # spent 12µs making 1 call to Encode::Alias::define_alias | |||
| 210 | # http://rt.cpan.org/Ticket/Display.html?id=36326 | |||
| 211 | define_alias( qr/^macintosh$/i => '"MacRoman"' ); # spent 11µs making 1 call to Encode::Alias::define_alias | |||
| 212 | ||||
| 213 | # Ououououou. gone. They are differente! | |||
| 214 | # define_alias( qr/\bmacRomanian$/i => '"macRumanian"'); | |||
| 215 | ||||
| 216 | # Standardize on the dashed versions. | |||
| 217 | define_alias( qr/\bkoi8[\s\-_]*([ru])$/i => '"koi8-$1"' ); # spent 14µs making 1 call to Encode::Alias::define_alias | |||
| 218 | ||||
| 219 | unless ($Encode::ON_EBCDIC) { | |||
| 220 | ||||
| 221 | # for Encode::CN | |||
| 222 | define_alias( qr/\beuc.*cn$/i => '"euc-cn"' ); # spent 17µs making 1 call to Encode::Alias::define_alias | |||
| 223 | define_alias( qr/\bcn.*euc$/i => '"euc-cn"' ); # spent 13µs making 1 call to Encode::Alias::define_alias | |||
| 224 | ||||
| 225 | # define_alias( qr/\bGB[- ]?(\d+)$/i => '"euc-cn"' ) | |||
| 226 | # CP936 doesn't have vendor-addon for GBK, so they're identical. | |||
| 227 | define_alias( qr/^gbk$/i => '"cp936"' ); # spent 13µs making 1 call to Encode::Alias::define_alias | |||
| 228 | ||||
| 229 | # This fixes gb2312 vs. euc-cn confusion, practically | |||
| 230 | define_alias( qr/\bGB[-_ ]?2312(?!-?raw)/i => '"euc-cn"' ); # spent 8µs making 1 call to Encode::Alias::define_alias | |||
| 231 | ||||
| 232 | # for Encode::JP | |||
| 233 | define_alias( qr/\bjis$/i => '"7bit-jis"' ); # spent 13µs making 1 call to Encode::Alias::define_alias | |||
| 234 | define_alias( qr/\beuc.*jp$/i => '"euc-jp"' ); # spent 8µs making 1 call to Encode::Alias::define_alias | |||
| 235 | define_alias( qr/\bjp.*euc$/i => '"euc-jp"' ); # spent 13µs making 1 call to Encode::Alias::define_alias | |||
| 236 | define_alias( qr/\bujis$/i => '"euc-jp"' ); # spent 11µs making 1 call to Encode::Alias::define_alias | |||
| 237 | define_alias( qr/\bshift.*jis$/i => '"shiftjis"' ); # spent 13µs making 1 call to Encode::Alias::define_alias | |||
| 238 | define_alias( qr/\bsjis$/i => '"shiftjis"' ); # spent 8µs making 1 call to Encode::Alias::define_alias | |||
| 239 | define_alias( qr/\bwindows-31j$/i => '"cp932"' ); # spent 17µs making 1 call to Encode::Alias::define_alias | |||
| 240 | ||||
| 241 | # for Encode::KR | |||
| 242 | define_alias( qr/\beuc.*kr$/i => '"euc-kr"' ); # spent 9µs making 1 call to Encode::Alias::define_alias | |||
| 243 | define_alias( qr/\bkr.*euc$/i => '"euc-kr"' ); # spent 17µs making 1 call to Encode::Alias::define_alias | |||
| 244 | ||||
| 245 | # This fixes ksc5601 vs. euc-kr confusion, practically | |||
| 246 | define_alias( qr/(?:x-)?uhc$/i => '"cp949"' ); # spent 16µs making 1 call to Encode::Alias::define_alias | |||
| 247 | define_alias( qr/(?:x-)?windows-949$/i => '"cp949"' ); # spent 12µs making 1 call to Encode::Alias::define_alias | |||
| 248 | define_alias( qr/\bks_c_5601-1987$/i => '"cp949"' ); # spent 14µs making 1 call to Encode::Alias::define_alias | |||
| 249 | ||||
| 250 | # for Encode::TW | |||
| 251 | define_alias( qr/\bbig-?5$/i => '"big5-eten"' ); # spent 13µs making 1 call to Encode::Alias::define_alias | |||
| 252 | define_alias( qr/\bbig5-?et(?:en)?$/i => '"big5-eten"' ); # spent 9µs making 1 call to Encode::Alias::define_alias | |||
| 253 | define_alias( qr/\btca[-_]?big5$/i => '"big5-eten"' ); # spent 17µs making 1 call to Encode::Alias::define_alias | |||
| 254 | define_alias( qr/\bbig5-?hk(?:scs)?$/i => '"big5-hkscs"' ); # spent 13µs making 1 call to Encode::Alias::define_alias | |||
| 255 | define_alias( qr/\bhk(?:scs)?[-_]?big5$/i => '"big5-hkscs"' ); # spent 13µs making 1 call to Encode::Alias::define_alias | |||
| 256 | } | |||
| 257 | ||||
| 258 | # utf8 is blessed :) | |||
| 259 | define_alias( qr/\bUTF-8$/i => '"utf-8-strict"' ); # spent 14µs making 1 call to Encode::Alias::define_alias | |||
| 260 | ||||
| 261 | # At last, Map white space and _ to '-' | |||
| 262 | define_alias( qr/^(\S+)[\s_]+(.*)$/i => '"$1-$2"' ); # spent 13µs making 1 call to Encode::Alias::define_alias | |||
| 263 | } | |||
| 264 | ||||
| 265 | 1 | 25µs | 25µs | 1; |
| 266 | __END__ | |||
| 267 | ||||
| 268 | # TODO: HP-UX '8' encodings arabic8 greek8 hebrew8 kana8 thai8 turkish8 | |||
| 269 | # TODO: HP-UX '15' encodings japanese15 korean15 roi15 | |||
| 270 | # TODO: Cyrillic encoding ISO-IR-111 (useful?) | |||
| 271 | # TODO: Armenian encoding ARMSCII-8 | |||
| 272 | # TODO: Hebrew encoding ISO-8859-8-1 | |||
| 273 | # TODO: Thai encoding TCVN | |||
| 274 | # TODO: Vietnamese encodings VPS | |||
| 275 | # TODO: Mac Asian+African encodings: Arabic Armenian Bengali Burmese | |||
| 276 | # ChineseSimp ChineseTrad Devanagari Ethiopic ExtArabic | |||
| 277 | # Farsi Georgian Gujarati Gurmukhi Hebrew Japanese | |||
| 278 | # Kannada Khmer Korean Laotian Malayalam Mongolian | |||
| 279 | # Oriya Sinhalese Symbol Tamil Telugu Tibetan Vietnamese | |||
| 280 | ||||
| 281 | =head1 NAME | |||
| 282 | ||||
| 283 | Encode::Alias - alias definitions to encodings | |||
| 284 | ||||
| 285 | =head1 SYNOPSIS | |||
| 286 | ||||
| 287 | use Encode; | |||
| 288 | use Encode::Alias; | |||
| 289 | define_alias( newName => ENCODING); | |||
| 290 | ||||
| 291 | =head1 DESCRIPTION | |||
| 292 | ||||
| 293 | Allows newName to be used as an alias for ENCODING. ENCODING may be | |||
| 294 | either the name of an encoding or an encoding object (as described | |||
| 295 | in L<Encode>). | |||
| 296 | ||||
| 297 | Currently I<newName> can be specified in the following ways: | |||
| 298 | ||||
| 299 | =over 4 | |||
| 300 | ||||
| 301 | =item As a simple string. | |||
| 302 | ||||
| 303 | =item As a qr// compiled regular expression, e.g.: | |||
| 304 | ||||
| 305 | define_alias( qr/^iso8859-(\d+)$/i => '"iso-8859-$1"' ); | |||
| 306 | ||||
| 307 | In this case, if I<ENCODING> is not a reference, it is C<eval>-ed | |||
| 308 | in order to allow C<$1> etc. to be substituted. The example is one | |||
| 309 | way to alias names as used in X11 fonts to the MIME names for the | |||
| 310 | iso-8859-* family. Note the double quotes inside the single quotes. | |||
| 311 | ||||
| 312 | (or, you don't have to do this yourself because this example is predefined) | |||
| 313 | ||||
| 314 | If you are using a regex here, you have to use the quotes as shown or | |||
| 315 | it won't work. Also note that regex handling is tricky even for the | |||
| 316 | experienced. Use this feature with caution. | |||
| 317 | ||||
| 318 | =item As a code reference, e.g.: | |||
| 319 | ||||
| 320 | define_alias( sub {shift =~ /^iso8859-(\d+)$/i ? "iso-8859-$1" : undef } ); | |||
| 321 | ||||
| 322 | The same effect as the example above in a different way. The coderef | |||
| 323 | takes the alias name as an argument and returns a canonical name on | |||
| 324 | success or undef if not. Note the second argument is not required. | |||
| 325 | Use this with even more caution than the regex version. | |||
| 326 | ||||
| 327 | =back | |||
| 328 | ||||
| 329 | =head3 Changes in code reference aliasing | |||
| 330 | ||||
| 331 | As of Encode 1.87, the older form | |||
| 332 | ||||
| 333 | define_alias( sub { return /^iso8859-(\d+)$/i ? "iso-8859-$1" : undef } ); | |||
| 334 | ||||
| 335 | no longer works. | |||
| 336 | ||||
| 337 | Encode up to 1.86 internally used "local $_" to implement ths older | |||
| 338 | form. But consider the code below; | |||
| 339 | ||||
| 340 | use Encode; | |||
| 341 | $_ = "eeeee" ; | |||
| 342 | while (/(e)/g) { | |||
| 343 | my $utf = decode('aliased-encoding-name', $1); | |||
| 344 | print "position:",pos,"\n"; | |||
| 345 | } | |||
| 346 | ||||
| 347 | Prior to Encode 1.86 this fails because of "local $_". | |||
| 348 | ||||
| 349 | =head2 Alias overloading | |||
| 350 | ||||
| 351 | You can override predefined aliases by simply applying define_alias(). | |||
| 352 | The new alias is always evaluated first, and when necessary, | |||
| 353 | define_alias() flushes the internal cache to make the new definition | |||
| 354 | available. | |||
| 355 | ||||
| 356 | # redirect SHIFT_JIS to MS/IBM Code Page 932, which is a | |||
| 357 | # superset of SHIFT_JIS | |||
| 358 | ||||
| 359 | define_alias( qr/shift.*jis$/i => '"cp932"' ); | |||
| 360 | define_alias( qr/sjis$/i => '"cp932"' ); | |||
| 361 | ||||
| 362 | If you want to zap all predefined aliases, you can use | |||
| 363 | ||||
| 364 | Encode::Alias->undef_aliases; | |||
| 365 | ||||
| 366 | to do so. And | |||
| 367 | ||||
| 368 | Encode::Alias->init_aliases; | |||
| 369 | ||||
| 370 | gets the factory settings back. | |||
| 371 | ||||
| 372 | =head1 SEE ALSO | |||
| 373 | ||||
| 374 | L<Encode>, L<Encode::Supported> | |||
| 375 | ||||
| 376 | =cut | |||
| 377 |