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 | define_alias | Encode::Alias::
1 | 1 | 1 | 175µs | 806µs | init_aliases | Encode::Alias::
1 | 1 | 1 | 8µs | 8µs | undef_aliases | Encode::Alias::
0 | 0 | 0 | 0s | 0s | BEGIN | Encode::Alias::
0 | 0 | 0 | 0s | 0s | find_alias | Encode::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 | 44 | 49µs | 1µs | while (@_) { |
82 | 53 | 99µs | 2µs | my ( $alias, $name ) = splice( @_, 0, 2 ); |
83 | 53 | 63µs | 1µs | unshift( @Alias, $alias => $name ); # newer one has precedence |
84 | 53 | 59µs | 1µs | if ( ref($alias) ) { |
85 | ||||
86 | # clear %Alias cache to allow overrides | |||
87 | 46 | 22µs | 480ns | my @a = keys %Alias; |
88 | 46 | 42µs | 909ns | 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 | 7 | 1µs | 171ns | DEBUG and warn "delete \$Alias\{$alias\}"; |
101 | 7 | 16µs | 2µs | 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 | 1 | 500ns | 500ns | @Alias = (); |
127 | 1 | 2µs | 2µs | %Alias = (); |
128 | } | |||
129 | ||||
130 | # spent 806µs (175+631) within Encode::Alias::init_aliases which was called
# once (175µs+631µs) at line 123 | |||
131 | 1 | 600ns | 600ns | require Encode; |
132 | 1 | 7µs | 7µs | undef_aliases(); # spent 8µs making 1 call to Encode::Alias::undef_aliases |
133 | ||||
134 | # Try all-lower-case version should all else fails | |||
135 | 1 | 12µs | 12µs | define_alias( qr/^(.*)$/ => '"\L$1"' ); # spent 16µs making 1 call to Encode::Alias::define_alias |
136 | ||||
137 | # UTF/UCS stuff | |||
138 | 1 | 16µs | 16µs | define_alias( qr/^(unicode-1-1-)?UTF-?7$/i => '"UTF-7"' ); # spent 15µs making 1 call to Encode::Alias::define_alias |
139 | 1 | 6µs | 6µs | define_alias( qr/^UCS-?2-?LE$/i => '"UCS-2LE"' ); # spent 10µs making 1 call to Encode::Alias::define_alias |
140 | 1 | 12µs | 12µs | define_alias( # spent 26µs making 1 call to Encode::Alias::define_alias |
141 | qr/^UCS-?2-?(BE)?$/i => '"UCS-2BE"', | |||
142 | qr/^UCS-?4-?(BE|LE)?$/i => 'uc("UTF-32$1")', | |||
143 | qr/^iso-10646-1$/i => '"UCS-2BE"' | |||
144 | ); | |||
145 | 1 | 18µs | 18µs | 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-$1"', | |||
149 | ); | |||
150 | ||||
151 | # ASCII | |||
152 | 1 | 11µs | 11µs | define_alias( qr/^(?:US-?)ascii$/i => '"ascii"' ); # spent 9µs making 1 call to Encode::Alias::define_alias |
153 | 1 | 9µs | 9µs | define_alias( 'C' => 'ascii' ); # spent 17µs making 1 call to Encode::Alias::define_alias |
154 | 1 | 7µs | 7µs | define_alias( qr/\b(?:ISO[-_]?)?646(?:[-_]?US)?$/i => '"ascii"' ); # spent 13µs making 1 call to Encode::Alias::define_alias |
155 | ||||
156 | # Allow variants of iso-8859-1 etc. | |||
157 | 1 | 7µs | 7µs | define_alias( qr/\biso[-_]?(\d+)[-_](\d+)$/i => '"iso-$1-$2"' ); # spent 10µs making 1 call to Encode::Alias::define_alias |
158 | ||||
159 | # At least HP-UX has these. | |||
160 | 1 | 5µs | 5µs | define_alias( qr/\biso8859(\d+)$/i => '"iso-8859-$1"' ); # spent 10µs making 1 call to Encode::Alias::define_alias |
161 | ||||
162 | # More HP stuff. | |||
163 | 1 | 5µs | 5µs | define_alias( # spent 8µs making 1 call to Encode::Alias::define_alias |
164 | qr/\b(?:hp-)?(arabic|greek|hebrew|kana|roman|thai|turkish)8$/i => | |||
165 | '"${1}8"' ); | |||
166 | ||||
167 | # The Official name of ASCII. | |||
168 | 1 | 9µs | 9µs | define_alias( qr/\bANSI[-_]?X3\.4[-_]?1968$/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 | 1 | 10µs | 10µs | define_alias( qr/^(.+)\@euro$/i => '"$1"' ); # spent 13µs making 1 call to Encode::Alias::define_alias |
174 | ||||
175 | 1 | 11µs | 11µs | define_alias( qr/\b(?:iso[-_]?)?latin[-_]?(\d+)$/i => # spent 15µs making 1 call to Encode::Alias::define_alias |
176 | 'defined $Encode::Alias::Latin2iso[$1] ? "iso-8859-$Encode::Alias::Latin2iso[$1]" : undef' | |||
177 | ); | |||
178 | ||||
179 | 1 | 10µs | 10µs | define_alias( # spent 14µs making 1 call to Encode::Alias::define_alias |
180 | qr/\bwin(latin[12]|cyrillic|baltic|greek|turkish| | |||
181 | hebrew|arabic|baltic|vietnamese)$/ix => | |||
182 | '"cp" . $Encode::Alias::Winlatin2cp{lc($1)}' | |||
183 | ); | |||
184 | ||||
185 | # Common names for non-latin preferred MIME names | |||
186 | 1 | 11µs | 11µs | define_alias( # spent 51µs making 1 call to Encode::Alias::define_alias |
187 | 'ascii' => 'US-ascii', | |||
188 | 'cyrillic' => 'iso-8859-5', | |||
189 | 'arabic' => 'iso-8859-6', | |||
190 | 'greek' => 'iso-8859-7', | |||
191 | 'hebrew' => 'iso-8859-8', | |||
192 | 'thai' => 'iso-8859-11', | |||
193 | ); | |||
194 | # RT #20781 | |||
195 | 1 | 7µs | 7µs | define_alias(qr/\btis-?620\b/i => '"iso-8859-11"'); # spent 9µs making 1 call to Encode::Alias::define_alias |
196 | ||||
197 | # At least AIX has IBM-NNN (surprisingly...) instead of cpNNN. | |||
198 | # And Microsoft has their own naming (again, surprisingly). | |||
199 | # And windows-* is registered in IANA! | |||
200 | 1 | 13µs | 13µs | define_alias( # spent 16µs making 1 call to Encode::Alias::define_alias |
201 | qr/\b(?:cp|ibm|ms|windows)[-_ ]?(\d{2,4})$/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 | 1 | 9µs | 9µs | define_alias( qr/^mac_(.*)$/i => '"mac$1"' ); # spent 12µs making 1 call to Encode::Alias::define_alias |
210 | # http://rt.cpan.org/Ticket/Display.html?id=36326 | |||
211 | 1 | 10µs | 10µs | define_alias( qr/^macintosh$/i => '"MacRoman"' ); # spent 11µs making 1 call to Encode::Alias::define_alias |
212 | ||||
213 | # Ououououou. gone. They are differente! | |||
214 | # define_alias( qr/\bmacRomanian$/i => '"macRumanian"'); | |||
215 | ||||
216 | # Standardize on the dashed versions. | |||
217 | 1 | 5µs | 5µs | define_alias( qr/\bkoi8[\s\-_]*([ru])$/i => '"koi8-$1"' ); # spent 14µs making 1 call to Encode::Alias::define_alias |
218 | ||||
219 | 1 | 700ns | 700ns | unless ($Encode::ON_EBCDIC) { |
220 | ||||
221 | # for Encode::CN | |||
222 | 1 | 10µs | 10µs | define_alias( qr/\beuc.*cn$/i => '"euc-cn"' ); # spent 17µs making 1 call to Encode::Alias::define_alias |
223 | 1 | 10µs | 10µs | define_alias( qr/\bcn.*euc$/i => '"euc-cn"' ); # spent 13µs making 1 call to Encode::Alias::define_alias |
224 | ||||
225 | # define_alias( qr/\bGB[- ]?(\d+)$/i => '"euc-cn"' ) | |||
226 | # CP936 doesn't have vendor-addon for GBK, so they're identical. | |||
227 | 1 | 10µs | 10µs | define_alias( qr/^gbk$/i => '"cp936"' ); # spent 13µs making 1 call to Encode::Alias::define_alias |
228 | ||||
229 | # This fixes gb2312 vs. euc-cn confusion, practically | |||
230 | 1 | 5µs | 5µs | 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 | 1 | 10µs | 10µs | define_alias( qr/\bjis$/i => '"7bit-jis"' ); # spent 13µs making 1 call to Encode::Alias::define_alias |
234 | 1 | 10µs | 10µs | define_alias( qr/\beuc.*jp$/i => '"euc-jp"' ); # spent 8µs making 1 call to Encode::Alias::define_alias |
235 | 1 | 12µs | 12µs | define_alias( qr/\bjp.*euc$/i => '"euc-jp"' ); # spent 13µs making 1 call to Encode::Alias::define_alias |
236 | 1 | 5µs | 5µs | define_alias( qr/\bujis$/i => '"euc-jp"' ); # spent 11µs making 1 call to Encode::Alias::define_alias |
237 | 1 | 9µs | 9µs | define_alias( qr/\bshift.*jis$/i => '"shiftjis"' ); # spent 13µs making 1 call to Encode::Alias::define_alias |
238 | 1 | 5µs | 5µs | define_alias( qr/\bsjis$/i => '"shiftjis"' ); # spent 8µs making 1 call to Encode::Alias::define_alias |
239 | 1 | 14µs | 14µs | define_alias( qr/\bwindows-31j$/i => '"cp932"' ); # spent 17µs making 1 call to Encode::Alias::define_alias |
240 | ||||
241 | # for Encode::KR | |||
242 | 1 | 14µs | 14µs | define_alias( qr/\beuc.*kr$/i => '"euc-kr"' ); # spent 9µs making 1 call to Encode::Alias::define_alias |
243 | 1 | 10µs | 10µs | define_alias( qr/\bkr.*euc$/i => '"euc-kr"' ); # spent 17µs making 1 call to Encode::Alias::define_alias |
244 | ||||
245 | # This fixes ksc5601 vs. euc-kr confusion, practically | |||
246 | 1 | 11µs | 11µs | define_alias( qr/(?:x-)?uhc$/i => '"cp949"' ); # spent 16µs making 1 call to Encode::Alias::define_alias |
247 | 1 | 9µs | 9µs | define_alias( qr/(?:x-)?windows-949$/i => '"cp949"' ); # spent 12µs making 1 call to Encode::Alias::define_alias |
248 | 1 | 10µs | 10µs | define_alias( qr/\bks_c_5601-1987$/i => '"cp949"' ); # spent 14µs making 1 call to Encode::Alias::define_alias |
249 | ||||
250 | # for Encode::TW | |||
251 | 1 | 9µs | 9µs | define_alias( qr/\bbig-?5$/i => '"big5-eten"' ); # spent 13µs making 1 call to Encode::Alias::define_alias |
252 | 1 | 14µs | 14µs | define_alias( qr/\bbig5-?et(?:en)?$/i => '"big5-eten"' ); # spent 9µs making 1 call to Encode::Alias::define_alias |
253 | 1 | 14µs | 14µs | define_alias( qr/\btca[-_]?big5$/i => '"big5-eten"' ); # spent 17µs making 1 call to Encode::Alias::define_alias |
254 | 1 | 10µs | 10µs | define_alias( qr/\bbig5-?hk(?:scs)?$/i => '"big5-hkscs"' ); # spent 13µs making 1 call to Encode::Alias::define_alias |
255 | 1 | 10µs | 10µs | define_alias( qr/\bhk(?:scs)?[-_]?big5$/i => '"big5-hkscs"' ); # spent 13µs making 1 call to Encode::Alias::define_alias |
256 | } | |||
257 | ||||
258 | # utf8 is blessed :) | |||
259 | 1 | 11µs | 11µs | define_alias( qr/\bUTF-8$/i => '"utf-8-strict"' ); # spent 14µs making 1 call to Encode::Alias::define_alias |
260 | ||||
261 | # At last, Map white space and _ to '-' | |||
262 | 1 | 10µs | 10µs | 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 |