package Encode::Alias; use strict; no warnings 'redefine'; use Encode; our $VERSION = do { my @r = (q$Revision: 1.38 $ =~ /\d+/g); sprintf "%d."."%02d" x $#r, @r }; sub DEBUG () { 0 } use base qw(Exporter); # Public, encouraged API is exported by default our @EXPORT = qw ( define_alias find_alias ); our @Alias; # ordered matching list our %Alias; # cached known aliases sub find_alias { my $class = shift; my $find = shift; unless (exists $Alias{$find}) { $Alias{$find} = undef; # Recursion guard for (my $i=0; $i < @Alias; $i += 2) { my $alias = $Alias[$i]; my $val = $Alias[$i+1]; my $new; if (ref($alias) eq 'Regexp' && $find =~ $alias) { DEBUG and warn "eval $val"; $new = eval $val; DEBUG and $@ and warn "$val, $@"; } elsif (ref($alias) eq 'CODE') { DEBUG and warn "$alias", "->", "($find)"; $new = $alias->($find); } elsif (lc($find) eq lc($alias)) { $new = $val; } if (defined($new)) { next if $new eq $find; # avoid (direct) recursion on bugs DEBUG and warn "$alias, $new"; my $enc = (ref($new)) ? $new : Encode::find_encoding($new); if ($enc) { $Alias{$find} = $enc; last; } } } } if (DEBUG){ my $name; if (my $e = $Alias{$find}){ $name = $e->name; }else{ $name = ""; } warn "find_alias($class, $find)->name = $name"; } return $Alias{$find}; } sub define_alias { while (@_) { my ($alias,$name) = splice(@_,0,2); unshift(@Alias, $alias => $name); # newer one has precedence # clear %Alias cache to allow overrides if (ref($alias)){ my @a = keys %Alias; for my $k (@a){ if (ref($alias) eq 'Regexp' && $k =~ $alias) { DEBUG and warn "delete \$Alias\{$k\}"; delete $Alias{$k}; } elsif (ref($alias) eq 'CODE') { DEBUG and warn "delete \$Alias\{$k\}"; delete $Alias{$alias->($name)}; } } }else{ DEBUG and warn "delete \$Alias\{$alias\}"; delete $Alias{$alias}; } } } # Allow latin-1 style names as well # 0 1 2 3 4 5 6 7 8 9 10 our @Latin2iso = ( 0, 1, 2, 3, 4, 9, 10, 13, 14, 15, 16 ); # Allow winlatin1 style names as well our %Winlatin2cp = ( 'latin1' => 1252, 'latin2' => 1250, 'cyrillic' => 1251, 'greek' => 1253, 'turkish' => 1254, 'hebrew' => 1255, 'arabic' => 1256, 'baltic' => 1257, 'vietnamese' => 1258, ); init_aliases(); sub undef_aliases{ @Alias = (); %Alias = (); } sub init_aliases { undef_aliases(); # Try all-lower-case version should all else fails define_alias( qr/^(.*)$/ => '"\L$1"' ); # UTF/UCS stuff define_alias( qr/^UTF-?7$/i => '"UTF-7"'); define_alias( qr/^UCS-?2-?LE$/i => '"UCS-2LE"' ); define_alias( qr/^UCS-?2-?(BE)?$/i => '"UCS-2BE"', qr/^UCS-?4-?(BE|LE)?$/i => 'uc("UTF-32$1")', qr/^iso-10646-1$/i => '"UCS-2BE"' ); define_alias( qr/^UTF(16|32)-?BE$/i => '"UTF-$1BE"', qr/^UTF(16|32)-?LE$/i => '"UTF-$1LE"', qr/^UTF(16|32)$/i => '"UTF-$1"', ); # ASCII define_alias(qr/^(?:US-?)ascii$/i => '"ascii"'); define_alias('C' => 'ascii'); define_alias(qr/\bISO[-_]?646[-_]?US$/i => '"ascii"'); # Allow variants of iso-8859-1 etc. define_alias( qr/\biso[-_]?(\d+)[-_](\d+)$/i => '"iso-$1-$2"' ); # At least HP-UX has these. define_alias( qr/\biso8859(\d+)$/i => '"iso-8859-$1"' ); # More HP stuff. define_alias( qr/\b(?:hp-)?(arabic|greek|hebrew|kana|roman|thai|turkish)8$/i => '"${1}8"' ); # The Official name of ASCII. define_alias( qr/\bANSI[-_]?X3\.4[-_]?1968$/i => '"ascii"' ); # This is a font issue, not an encoding issue. # (The currency symbol of the Latin 1 upper half # has been redefined as the euro symbol.) define_alias( qr/^(.+)\@euro$/i => '"$1"' ); define_alias( qr/\b(?:iso[-_]?)?latin[-_]?(\d+)$/i => 'defined $Encode::Alias::Latin2iso[$1] ? "iso-8859-$Encode::Alias::Latin2iso[$1]" : undef' ); define_alias( qr/\bwin(latin[12]|cyrillic|baltic|greek|turkish| hebrew|arabic|baltic|vietnamese)$/ix => '"cp" . $Encode::Alias::Winlatin2cp{lc($1)}' ); # Common names for non-latin prefered MIME names define_alias( 'ascii' => 'US-ascii', 'cyrillic' => 'iso-8859-5', 'arabic' => 'iso-8859-6', 'greek' => 'iso-8859-7', 'hebrew' => 'iso-8859-8', 'thai' => 'iso-8859-11', 'tis620' => 'iso-8859-11', ); # At least AIX has IBM-NNN (surprisingly...) instead of cpNNN. # And Microsoft has their own naming (again, surprisingly). # And windows-* is registered in IANA! define_alias( qr/\b(?:cp|ibm|ms|windows)[-_ ]?(\d{2,4})$/i => '"cp$1"'); # Sometimes seen with a leading zero. # define_alias( qr/\bcp037\b/i => '"cp37"'); # Mac Mappings # predefined in *.ucm; unneeded # define_alias( qr/\bmacIcelandic$/i => '"macIceland"'); define_alias( qr/^mac_(.*)$/i => '"mac$1"'); # Ououououou. gone. They are differente! # define_alias( qr/\bmacRomanian$/i => '"macRumanian"'); # Standardize on the dashed versions. # define_alias( qr/\butf8$/i => '"utf-8"' ); define_alias( qr/\bkoi8[\s-_]*([ru])$/i => '"koi8-$1"' ); unless ($Encode::ON_EBCDIC){ # for Encode::CN define_alias( qr/\beuc.*cn$/i => '"euc-cn"' ); define_alias( qr/\bcn.*euc$/i => '"euc-cn"' ); # define_alias( qr/\bGB[- ]?(\d+)$/i => '"euc-cn"' ) # CP936 doesn't have vendor-addon for GBK, so they're identical. define_alias( qr/^gbk$/i => '"cp936"'); # This fixes gb2312 vs. euc-cn confusion, practically define_alias( qr/\bGB[-_ ]?2312(?!-?raw)/i => '"euc-cn"' ); # for Encode::JP define_alias( qr/\bjis$/i => '"7bit-jis"' ); define_alias( qr/\beuc.*jp$/i => '"euc-jp"' ); define_alias( qr/\bjp.*euc$/i => '"euc-jp"' ); define_alias( qr/\bujis$/i => '"euc-jp"' ); define_alias( qr/\bshift.*jis$/i => '"shiftjis"' ); define_alias( qr/\bsjis$/i => '"shiftjis"' ); # for Encode::KR define_alias( qr/\beuc.*kr$/i => '"euc-kr"' ); define_alias( qr/\bkr.*euc$/i => '"euc-kr"' ); # This fixes ksc5601 vs. euc-kr confusion, practically define_alias( qr/(?:x-)?uhc$/i => '"cp949"' ); define_alias( qr/(?:x-)?windows-949$/i => '"cp949"' ); define_alias( qr/\bks_c_5601-1987$/i => '"cp949"' ); # for Encode::TW define_alias( qr/\bbig-?5$/i => '"big5-eten"' ); define_alias( qr/\bbig5-?et(?:en)?$/i => '"big5-eten"' ); define_alias( qr/\btca[-_]?big5$/i => '"big5-eten"' ); define_alias( qr/\bbig5-?hk(?:scs)?$/i => '"big5-hkscs"' ); define_alias( qr/\bhk(?:scs)?[-_]?big5$/i => '"big5-hkscs"' ); } # utf8 is blessed :) define_alias( qr/^UTF-8$/i => '"utf8"',); # At last, Map white space and _ to '-' define_alias( qr/^(\S+)[\s_]+(.*)$/i => '"$1-$2"' ); } 1; __END__ # TODO: HP-UX '8' encodings arabic8 greek8 hebrew8 kana8 thai8 turkish8 # TODO: HP-UX '15' encodings japanese15 korean15 roi15 # TODO: Cyrillic encoding ISO-IR-111 (useful?) # TODO: Armenian encoding ARMSCII-8 # TODO: Hebrew encoding ISO-8859-8-1 # TODO: Thai encoding TCVN # TODO: Vietnamese encodings VPS # TODO: Mac Asian+African encodings: Arabic Armenian Bengali Burmese # ChineseSimp ChineseTrad Devanagari Ethiopic ExtArabic # Farsi Georgian Gujarati Gurmukhi Hebrew Japanese # Kannada Khmer Korean Laotian Malayalam Mongolian # Oriya Sinhalese Symbol Tamil Telugu Tibetan Vietnamese =head1 NAME Encode::Alias - alias definitions to encodings =head1 SYNOPSIS use Encode; use Encode::Alias; define_alias( newName => ENCODING); =head1 DESCRIPTION Allows newName to be used as an alias for ENCODING. ENCODING may be either the name of an encoding or an encoding object (as described in L). Currently I can be specified in the following ways: =over 4 =item As a simple string. =item As a qr// compiled regular expression, e.g.: define_alias( qr/^iso8859-(\d+)$/i => '"iso-8859-$1"' ); In this case, if I is not a reference, it is C-ed in order to allow C<$1> etc. to be substituted. The example is one way to alias names as used in X11 fonts to the MIME names for the iso-8859-* family. Note the double quotes inside the single quotes. (or, you don't have to do this yourself because this example is predefined) If you are using a regex here, you have to use the quotes as shown or it won't work. Also note that regex handling is tricky even for the experienced. Use this feature with caution. =item As a code reference, e.g.: define_alias( sub {shift =~ /^iso8859-(\d+)$/i ? "iso-8859-$1" : undef } ); The same effect as the example above in a different way. The coderef takes the alias name as an argument and returns a canonical name on success or undef if not. Note the second argument is not required. Use this with even more caution than the regex version. =back =head3 Changes in code reference aliasing As of Encode 1.87, the older form define_alias( sub { return /^iso8859-(\d+)$/i ? "iso-8859-$1" : undef } ); no longer works. Encode up to 1.86 internally used "local $_" to implement ths older form. But consider the code below; use Encode; $_ = "eeeee" ; while (/(e)/g) { my $utf = decode('aliased-encoding-name', $1); print "position:",pos,"\n"; } Prior to Encode 1.86 this fails because of "local $_". =head2 Alias overloading You can override predefined aliases by simply applying define_alias(). The new alias is always evaluated first, and when neccessary, define_alias() flushes the internal cache to make the new definition available. # redirect SHIFT_JIS to MS/IBM Code Page 932, which is a # superset of SHIFT_JIS define_alias( qr/shift.*jis$/i => '"cp932"' ); define_alias( qr/sjis$/i => '"cp932"' ); If you want to zap all predefined aliases, you can use Encode::Alias->undef_aliases; to do so. And Encode::Alias->init_aliases; gets the factory settings back. =head1 SEE ALSO L, L =cut