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diff --git a/Master/tlpkg/tlperl/lib/Encode.pm b/Master/tlpkg/tlperl/lib/Encode.pm new file mode 100644 index 00000000000..ac0123c89ec --- /dev/null +++ b/Master/tlpkg/tlperl/lib/Encode.pm @@ -0,0 +1,851 @@ +# +# $Id: Encode.pm,v 2.12 2005/09/08 14:17:17 dankogai Exp dankogai $ +# +package Encode; +use strict; +our $VERSION = sprintf "%d.%02d", q$Revision: 2.12 $ =~ /(\d+)/g; +sub DEBUG () { 0 } +use XSLoader (); +XSLoader::load(__PACKAGE__, $VERSION); + +require Exporter; +use base qw/Exporter/; + +# Public, encouraged API is exported by default + +our @EXPORT = qw( + decode decode_utf8 encode encode_utf8 + encodings find_encoding clone_encoding +); + +our @FB_FLAGS = qw(DIE_ON_ERR WARN_ON_ERR RETURN_ON_ERR LEAVE_SRC + PERLQQ HTMLCREF XMLCREF STOP_AT_PARTIAL); +our @FB_CONSTS = qw(FB_DEFAULT FB_CROAK FB_QUIET FB_WARN + FB_PERLQQ FB_HTMLCREF FB_XMLCREF); + +our @EXPORT_OK = + ( + qw( + _utf8_off _utf8_on define_encoding from_to is_16bit is_8bit + is_utf8 perlio_ok resolve_alias utf8_downgrade utf8_upgrade + ), + @FB_FLAGS, @FB_CONSTS, + ); + +our %EXPORT_TAGS = + ( + all => [ @EXPORT, @EXPORT_OK ], + fallbacks => [ @FB_CONSTS ], + fallback_all => [ @FB_CONSTS, @FB_FLAGS ], + ); + +# Documentation moved after __END__ for speed - NI-S + +our $ON_EBCDIC = (ord("A") == 193); + +use Encode::Alias; + +# Make a %Encoding package variable to allow a certain amount of cheating +our %Encoding; +our %ExtModule; +require Encode::Config; +eval { require Encode::ConfigLocal }; + +sub encodings +{ + my $class = shift; + my %enc; + if (@_ and $_[0] eq ":all"){ + %enc = ( %Encoding, %ExtModule ); + }else{ + %enc = %Encoding; + for my $mod (map {m/::/o ? $_ : "Encode::$_" } @_){ + DEBUG and warn $mod; + for my $enc (keys %ExtModule){ + $ExtModule{$enc} eq $mod and $enc{$enc} = $mod; + } + } + } + return + sort { lc $a cmp lc $b } + grep {!/^(?:Internal|Unicode|Guess)$/o} keys %enc; +} + +sub perlio_ok{ + my $obj = ref($_[0]) ? $_[0] : find_encoding($_[0]); + $obj->can("perlio_ok") and return $obj->perlio_ok(); + return 0; # safety net +} + +sub define_encoding +{ + my $obj = shift; + my $name = shift; + $Encoding{$name} = $obj; + my $lc = lc($name); + define_alias($lc => $obj) unless $lc eq $name; + while (@_){ + my $alias = shift; + define_alias($alias, $obj); + } + return $obj; +} + +sub getEncoding +{ + my ($class, $name, $skip_external) = @_; + + ref($name) && $name->can('renew') and return $name; + exists $Encoding{$name} and return $Encoding{$name}; + my $lc = lc $name; + exists $Encoding{$lc} and return $Encoding{$lc}; + + my $oc = $class->find_alias($name); + defined($oc) and return $oc; + $lc ne $name and $oc = $class->find_alias($lc); + defined($oc) and return $oc; + + unless ($skip_external) + { + if (my $mod = $ExtModule{$name} || $ExtModule{$lc}){ + $mod =~ s,::,/,g ; $mod .= '.pm'; + eval{ require $mod; }; + exists $Encoding{$name} and return $Encoding{$name}; + } + } + return; +} + +sub find_encoding($;$) +{ + my ($name, $skip_external) = @_; + return __PACKAGE__->getEncoding($name,$skip_external); +} + +sub resolve_alias($){ + my $obj = find_encoding(shift); + defined $obj and return $obj->name; + return; +} + +sub clone_encoding($){ + my $obj = find_encoding(shift); + ref $obj or return; + eval { require Storable }; + $@ and return; + return Storable::dclone($obj); +} + +sub encode($$;$) +{ + my ($name, $string, $check) = @_; + return undef unless defined $string; + $string .= '' if ref $string; # stringify; + $check ||=0; + my $enc = find_encoding($name); + unless(defined $enc){ + require Carp; + Carp::croak("Unknown encoding '$name'"); + } + my $octets = $enc->encode($string,$check); + $_[1] = $string if $check and !($check & LEAVE_SRC()); + return $octets; +} + +sub decode($$;$) +{ + my ($name,$octets,$check) = @_; + return undef unless defined $octets; + $octets .= '' if ref $octets; + $check ||=0; + my $enc = find_encoding($name); + unless(defined $enc){ + require Carp; + Carp::croak("Unknown encoding '$name'"); + } + my $string = $enc->decode($octets,$check); + $_[1] = $octets if $check and !($check & LEAVE_SRC()); + return $string; +} + +sub from_to($$$;$) +{ + my ($string,$from,$to,$check) = @_; + return undef unless defined $string; + $check ||=0; + my $f = find_encoding($from); + unless (defined $f){ + require Carp; + Carp::croak("Unknown encoding '$from'"); + } + my $t = find_encoding($to); + unless (defined $t){ + require Carp; + Carp::croak("Unknown encoding '$to'"); + } + my $uni = $f->decode($string,$check); + return undef if ($check && length($string)); + $string = $t->encode($uni,$check); + return undef if ($check && length($uni)); + return defined($_[0] = $string) ? length($string) : undef ; +} + +sub encode_utf8($) +{ + my ($str) = @_; + utf8::encode($str); + return $str; +} + +sub decode_utf8($;$) +{ + my ($str, $check) = @_; + if ($check){ + return decode("utf8", $str, $check); + }else{ + return decode("utf8", $str); + return $str; + } +} + +predefine_encodings(1); + +# +# This is to restore %Encoding if really needed; +# + +sub predefine_encodings{ + use Encode::Encoding; + no warnings 'redefine'; + my $use_xs = shift; + if ($ON_EBCDIC) { + # was in Encode::UTF_EBCDIC + package Encode::UTF_EBCDIC; + push @Encode::UTF_EBCDIC::ISA, 'Encode::Encoding'; + *decode = sub{ + my ($obj,$str,$chk) = @_; + my $res = ''; + for (my $i = 0; $i < length($str); $i++) { + $res .= + chr(utf8::unicode_to_native(ord(substr($str,$i,1)))); + } + $_[1] = '' if $chk; + return $res; + }; + *encode = sub{ + my ($obj,$str,$chk) = @_; + my $res = ''; + for (my $i = 0; $i < length($str); $i++) { + $res .= + chr(utf8::native_to_unicode(ord(substr($str,$i,1)))); + } + $_[1] = '' if $chk; + return $res; + }; + $Encode::Encoding{Unicode} = + bless {Name => "UTF_EBCDIC"} => "Encode::UTF_EBCDIC"; + } else { + package Encode::Internal; + push @Encode::Internal::ISA, 'Encode::Encoding'; + *decode = sub{ + my ($obj,$str,$chk) = @_; + utf8::upgrade($str); + $_[1] = '' if $chk; + return $str; + }; + *encode = \&decode; + $Encode::Encoding{Unicode} = + bless {Name => "Internal"} => "Encode::Internal"; + } + + { + # was in Encode::utf8 + package Encode::utf8; + push @Encode::utf8::ISA, 'Encode::Encoding'; + # + if ($use_xs){ + Encode::DEBUG and warn __PACKAGE__, " XS on"; + *decode = \&decode_xs; + *encode = \&encode_xs; + }else{ + Encode::DEBUG and warn __PACKAGE__, " XS off"; + *decode = sub{ + my ($obj,$octets,$chk) = @_; + my $str = Encode::decode_utf8($octets); + if (defined $str) { + $_[1] = '' if $chk; + return $str; + } + return undef; + }; + *encode = sub { + my ($obj,$string,$chk) = @_; + my $octets = Encode::encode_utf8($string); + $_[1] = '' if $chk; + return $octets; + }; + } + *cat_decode = sub{ # ($obj, $dst, $src, $pos, $trm, $chk) + my ($obj, undef, undef, $pos, $trm) = @_; # currently ignores $chk + my ($rdst, $rsrc, $rpos) = \@_[1,2,3]; + use bytes; + if ((my $npos = index($$rsrc, $trm, $pos)) >= 0) { + $$rdst .= substr($$rsrc, $pos, $npos - $pos + length($trm)); + $$rpos = $npos + length($trm); + return 1; + } + $$rdst .= substr($$rsrc, $pos); + $$rpos = length($$rsrc); + return ''; + }; + $Encode::Encoding{utf8} = + bless {Name => "utf8"} => "Encode::utf8"; + $Encode::Encoding{"utf-8-strict"} = + bless {Name => "utf-8-strict", strict_utf8 => 1 } => "Encode::utf8"; + } +} + +1; + +__END__ + +=head1 NAME + +Encode - character encodings + +=head1 SYNOPSIS + + use Encode; + +=head2 Table of Contents + +Encode consists of a collection of modules whose details are too big +to fit in one document. This POD itself explains the top-level APIs +and general topics at a glance. For other topics and more details, +see the PODs below: + + Name Description + -------------------------------------------------------- + Encode::Alias Alias definitions to encodings + Encode::Encoding Encode Implementation Base Class + Encode::Supported List of Supported Encodings + Encode::CN Simplified Chinese Encodings + Encode::JP Japanese Encodings + Encode::KR Korean Encodings + Encode::TW Traditional Chinese Encodings + -------------------------------------------------------- + +=head1 DESCRIPTION + +The C<Encode> module provides the interfaces between Perl's strings +and the rest of the system. Perl strings are sequences of +B<characters>. + +The repertoire of characters that Perl can represent is at least that +defined by the Unicode Consortium. On most platforms the ordinal +values of the characters (as returned by C<ord(ch)>) is the "Unicode +codepoint" for the character (the exceptions are those platforms where +the legacy encoding is some variant of EBCDIC rather than a super-set +of ASCII - see L<perlebcdic>). + +Traditionally, computer data has been moved around in 8-bit chunks +often called "bytes". These chunks are also known as "octets" in +networking standards. Perl is widely used to manipulate data of many +types - not only strings of characters representing human or computer +languages but also "binary" data being the machine's representation of +numbers, pixels in an image - or just about anything. + +When Perl is processing "binary data", the programmer wants Perl to +process "sequences of bytes". This is not a problem for Perl - as a +byte has 256 possible values, it easily fits in Perl's much larger +"logical character". + +=head2 TERMINOLOGY + +=over 2 + +=item * + +I<character>: a character in the range 0..(2**32-1) (or more). +(What Perl's strings are made of.) + +=item * + +I<byte>: a character in the range 0..255 +(A special case of a Perl character.) + +=item * + +I<octet>: 8 bits of data, with ordinal values 0..255 +(Term for bytes passed to or from a non-Perl context, e.g. a disk file.) + +=back + +=head1 PERL ENCODING API + +=over 2 + +=item $octets = encode(ENCODING, $string [, CHECK]) + +Encodes a string from Perl's internal form into I<ENCODING> and returns +a sequence of octets. ENCODING can be either a canonical name or +an alias. For encoding names and aliases, see L</"Defining Aliases">. +For CHECK, see L</"Handling Malformed Data">. + +For example, to convert a string from Perl's internal format to +iso-8859-1 (also known as Latin1), + + $octets = encode("iso-8859-1", $string); + +B<CAVEAT>: When you run C<$octets = encode("utf8", $string)>, then $octets +B<may not be equal to> $string. Though they both contain the same data, the utf8 flag +for $octets is B<always> off. When you encode anything, utf8 flag of +the result is always off, even when it contains completely valid utf8 +string. See L</"The UTF-8 flag"> below. + +If the $string is C<undef> then C<undef> is returned. + +=item $string = decode(ENCODING, $octets [, CHECK]) + +Decodes a sequence of octets assumed to be in I<ENCODING> into Perl's +internal form and returns the resulting string. As in encode(), +ENCODING can be either a canonical name or an alias. For encoding names +and aliases, see L</"Defining Aliases">. For CHECK, see +L</"Handling Malformed Data">. + +For example, to convert ISO-8859-1 data to a string in Perl's internal format: + + $string = decode("iso-8859-1", $octets); + +B<CAVEAT>: When you run C<$string = decode("utf8", $octets)>, then $string +B<may not be equal to> $octets. Though they both contain the same data, +the utf8 flag for $string is on unless $octets entirely consists of +ASCII data (or EBCDIC on EBCDIC machines). See L</"The UTF-8 flag"> +below. + +If the $string is C<undef> then C<undef> is returned. + +=item [$length =] from_to($octets, FROM_ENC, TO_ENC [, CHECK]) + +Converts B<in-place> data between two encodings. The data in $octets +must be encoded as octets and not as characters in Perl's internal +format. For example, to convert ISO-8859-1 data to Microsoft's CP1250 +encoding: + + from_to($octets, "iso-8859-1", "cp1250"); + +and to convert it back: + + from_to($octets, "cp1250", "iso-8859-1"); + +Note that because the conversion happens in place, the data to be +converted cannot be a string constant; it must be a scalar variable. + +from_to() returns the length of the converted string in octets on +success, I<undef> on error. + +B<CAVEAT>: The following operations look the same but are not quite so; + + from_to($data, "iso-8859-1", "utf8"); #1 + $data = decode("iso-8859-1", $data); #2 + +Both #1 and #2 make $data consist of a completely valid UTF-8 string +but only #2 turns utf8 flag on. #1 is equivalent to + + $data = encode("utf8", decode("iso-8859-1", $data)); + +See L</"The UTF-8 flag"> below. + +=item $octets = encode_utf8($string); + +Equivalent to C<$octets = encode("utf8", $string);> The characters +that comprise $string are encoded in Perl's internal format and the +result is returned as a sequence of octets. All possible +characters have a UTF-8 representation so this function cannot fail. + + +=item $string = decode_utf8($octets [, CHECK]); + +equivalent to C<$string = decode("utf8", $octets [, CHECK])>. +The sequence of octets represented by +$octets is decoded from UTF-8 into a sequence of logical +characters. Not all sequences of octets form valid UTF-8 encodings, so +it is possible for this call to fail. For CHECK, see +L</"Handling Malformed Data">. + +=back + +=head2 Listing available encodings + + use Encode; + @list = Encode->encodings(); + +Returns a list of the canonical names of the available encodings that +are loaded. To get a list of all available encodings including the +ones that are not loaded yet, say + + @all_encodings = Encode->encodings(":all"); + +Or you can give the name of a specific module. + + @with_jp = Encode->encodings("Encode::JP"); + +When "::" is not in the name, "Encode::" is assumed. + + @ebcdic = Encode->encodings("EBCDIC"); + +To find out in detail which encodings are supported by this package, +see L<Encode::Supported>. + +=head2 Defining Aliases + +To add a new alias to a given encoding, use: + + use Encode; + use Encode::Alias; + define_alias(newName => ENCODING); + +After that, newName can be used as an alias for ENCODING. +ENCODING may be either the name of an encoding or an +I<encoding object> + +But before you do so, make sure the alias is nonexistent with +C<resolve_alias()>, which returns the canonical name thereof. +i.e. + + Encode::resolve_alias("latin1") eq "iso-8859-1" # true + Encode::resolve_alias("iso-8859-12") # false; nonexistent + Encode::resolve_alias($name) eq $name # true if $name is canonical + +resolve_alias() does not need C<use Encode::Alias>; it can be +exported via C<use Encode qw(resolve_alias)>. + +See L<Encode::Alias> for details. + +=head1 Encoding via PerlIO + +If your perl supports I<PerlIO> (which is the default), you can use a PerlIO layer to decode +and encode directly via a filehandle. The following two examples +are totally identical in their functionality. + + # via PerlIO + open my $in, "<:encoding(shiftjis)", $infile or die; + open my $out, ">:encoding(euc-jp)", $outfile or die; + while(<$in>){ print $out $_; } + + # via from_to + open my $in, "<", $infile or die; + open my $out, ">", $outfile or die; + while(<$in>){ + from_to($_, "shiftjis", "euc-jp", 1); + print $out $_; + } + +Unfortunately, it may be that encodings are PerlIO-savvy. You can check +if your encoding is supported by PerlIO by calling the C<perlio_ok> +method. + + Encode::perlio_ok("hz"); # False + find_encoding("euc-cn")->perlio_ok; # True where PerlIO is available + + use Encode qw(perlio_ok); # exported upon request + perlio_ok("euc-jp") + +Fortunately, all encodings that come with Encode core are PerlIO-savvy +except for hz and ISO-2022-kr. For gory details, see +L<Encode::Encoding> and L<Encode::PerlIO>. + +=head1 Handling Malformed Data + +The optional I<CHECK> argument tells Encode what to do when it +encounters malformed data. Without CHECK, Encode::FB_DEFAULT ( == 0 ) +is assumed. + +As of version 2.12 Encode supports coderef values for CHECK. See below. + +=over 2 + +=item B<NOTE:> Not all encoding support this feature + +Some encodings ignore I<CHECK> argument. For example, +L<Encode::Unicode> ignores I<CHECK> and it always croaks on error. + +=back + +Now here is the list of I<CHECK> values available + +=over 2 + +=item I<CHECK> = Encode::FB_DEFAULT ( == 0) + +If I<CHECK> is 0, (en|de)code will put a I<substitution character> in +place of a malformed character. When you encode, E<lt>subcharE<gt> +will be used. When you decode the code point C<0xFFFD> is used. If +the data is supposed to be UTF-8, an optional lexical warning +(category utf8) is given. + +=item I<CHECK> = Encode::FB_CROAK ( == 1) + +If I<CHECK> is 1, methods will die on error immediately with an error +message. Therefore, when I<CHECK> is set to 1, you should trap the +error with eval{} unless you really want to let it die. + +=item I<CHECK> = Encode::FB_QUIET + +If I<CHECK> is set to Encode::FB_QUIET, (en|de)code will immediately +return the portion of the data that has been processed so far when an +error occurs. The data argument will be overwritten with everything +after that point (that is, the unprocessed part of data). This is +handy when you have to call decode repeatedly in the case where your +source data may contain partial multi-byte character sequences, +(i.e. you are reading with a fixed-width buffer). Here is a sample +code that does exactly this: + + my $buffer = ''; my $string = ''; + while(read $fh, $buffer, 256, length($buffer)){ + $string .= decode($encoding, $buffer, Encode::FB_QUIET); + # $buffer now contains the unprocessed partial character + } + +=item I<CHECK> = Encode::FB_WARN + +This is the same as above, except that it warns on error. Handy when +you are debugging the mode above. + +=item perlqq mode (I<CHECK> = Encode::FB_PERLQQ) + +=item HTML charref mode (I<CHECK> = Encode::FB_HTMLCREF) + +=item XML charref mode (I<CHECK> = Encode::FB_XMLCREF) + +For encodings that are implemented by Encode::XS, CHECK == +Encode::FB_PERLQQ turns (en|de)code into C<perlqq> fallback mode. + +When you decode, C<\xI<HH>> will be inserted for a malformed character, +where I<HH> is the hex representation of the octet that could not be +decoded to utf8. And when you encode, C<\x{I<HHHH>}> will be inserted, +where I<HHHH> is the Unicode ID of the character that cannot be found +in the character repertoire of the encoding. + +HTML/XML character reference modes are about the same, in place of +C<\x{I<HHHH>}>, HTML uses C<&#I<NNN>;> where I<NNN> is a decimal number and +XML uses C<&#xI<HHHH>;> where I<HHHH> is the hexadecimal number. + +In Encode 2.10 or later, C<LEAVE_SRC> is also implied. + +=item The bitmask + +These modes are actually set via a bitmask. Here is how the FB_XX +constants are laid out. You can import the FB_XX constants via +C<use Encode qw(:fallbacks)>; you can import the generic bitmask +constants via C<use Encode qw(:fallback_all)>. + + FB_DEFAULT FB_CROAK FB_QUIET FB_WARN FB_PERLQQ + DIE_ON_ERR 0x0001 X + WARN_ON_ERR 0x0002 X + RETURN_ON_ERR 0x0004 X X + LEAVE_SRC 0x0008 X + PERLQQ 0x0100 X + HTMLCREF 0x0200 + XMLCREF 0x0400 + +=back + +=head2 coderef for CHECK + +As of Encode 2.12 CHECK can also be a code reference which takes the +ord value of unmapped caharacter as an argument and returns a string +that represents the fallback character. For instance, + + $ascii = encode("ascii", $utf8, sub{ sprintf "<U+%04X>", shift }); + +Acts like FB_PERLQQ but E<lt>U+I<XXXX>E<gt> is used instead of +\x{I<XXXX>}. + +=head1 Defining Encodings + +To define a new encoding, use: + + use Encode qw(define_encoding); + define_encoding($object, 'canonicalName' [, alias...]); + +I<canonicalName> will be associated with I<$object>. The object +should provide the interface described in L<Encode::Encoding>. +If more than two arguments are provided then additional +arguments are taken as aliases for I<$object>. + +See L<Encode::Encoding> for more details. + +=head1 The UTF-8 flag + +Before the introduction of utf8 support in perl, The C<eq> operator +just compared the strings represented by two scalars. Beginning with +perl 5.8, C<eq> compares two strings with simultaneous consideration +of I<the utf8 flag>. To explain why we made it so, I will quote page +402 of C<Programming Perl, 3rd ed.> + +=over 2 + +=item Goal #1: + +Old byte-oriented programs should not spontaneously break on the old +byte-oriented data they used to work on. + +=item Goal #2: + +Old byte-oriented programs should magically start working on the new +character-oriented data when appropriate. + +=item Goal #3: + +Programs should run just as fast in the new character-oriented mode +as in the old byte-oriented mode. + +=item Goal #4: + +Perl should remain one language, rather than forking into a +byte-oriented Perl and a character-oriented Perl. + +=back + +Back when C<Programming Perl, 3rd ed.> was written, not even Perl 5.6.0 +was born and many features documented in the book remained +unimplemented for a long time. Perl 5.8 corrected this and the introduction +of the UTF-8 flag is one of them. You can think of this perl notion as of a +byte-oriented mode (utf8 flag off) and a character-oriented mode (utf8 +flag on). + +Here is how Encode takes care of the utf8 flag. + +=over 2 + +=item * + +When you encode, the resulting utf8 flag is always off. + +=item * + +When you decode, the resulting utf8 flag is on unless you can +unambiguously represent data. Here is the definition of +dis-ambiguity. + +After C<$utf8 = decode('foo', $octet);>, + + When $octet is... The utf8 flag in $utf8 is + --------------------------------------------- + In ASCII only (or EBCDIC only) OFF + In ISO-8859-1 ON + In any other Encoding ON + --------------------------------------------- + +As you see, there is one exception, In ASCII. That way you can assume +Goal #1. And with Encode Goal #2 is assumed but you still have to be +careful in such cases mentioned in B<CAVEAT> paragraphs. + +This utf8 flag is not visible in perl scripts, exactly for the same +reason you cannot (or you I<don't have to>) see if a scalar contains a +string, integer, or floating point number. But you can still peek +and poke these if you will. See the section below. + +=back + +=head2 Messing with Perl's Internals + +The following API uses parts of Perl's internals in the current +implementation. As such, they are efficient but may change. + +=over 2 + +=item is_utf8(STRING [, CHECK]) + +[INTERNAL] Tests whether the UTF-8 flag is turned on in the STRING. +If CHECK is true, also checks the data in STRING for being well-formed +UTF-8. Returns true if successful, false otherwise. + +As of perl 5.8.1, L<utf8> also has utf8::is_utf8(). + +=item _utf8_on(STRING) + +[INTERNAL] Turns on the UTF-8 flag in STRING. The data in STRING is +B<not> checked for being well-formed UTF-8. Do not use unless you +B<know> that the STRING is well-formed UTF-8. Returns the previous +state of the UTF-8 flag (so please don't treat the return value as +indicating success or failure), or C<undef> if STRING is not a string. + +=item _utf8_off(STRING) + +[INTERNAL] Turns off the UTF-8 flag in STRING. Do not use frivolously. +Returns the previous state of the UTF-8 flag (so please don't treat the +return value as indicating success or failure), or C<undef> if STRING is +not a string. + +=back + +=head1 UTF-8 vs. utf8 + + ....We now view strings not as sequences of bytes, but as sequences + of numbers in the range 0 .. 2**32-1 (or in the case of 64-bit + computers, 0 .. 2**64-1) -- Programming Perl, 3rd ed. + +That has been the perl's notion of UTF-8 but official UTF-8 is more +strict; Its ranges is much narrower (0 .. 10FFFF), some sequences are +not allowed (i.e. Those used in the surrogate pair, 0xFFFE, et al). + +Now that is overruled by Larry Wall himself. + + From: Larry Wall <larry@wall.org> + Date: December 04, 2004 11:51:58 JST + To: perl-unicode@perl.org + Subject: Re: Make Encode.pm support the real UTF-8 + Message-Id: <20041204025158.GA28754@wall.org> + + On Fri, Dec 03, 2004 at 10:12:12PM +0000, Tim Bunce wrote: + : I've no problem with 'utf8' being perl's unrestricted uft8 encoding, + : but "UTF-8" is the name of the standard and should give the + : corresponding behaviour. + + For what it's worth, that's how I've always kept them straight in my + head. + + Also for what it's worth, Perl 6 will mostly default to strict but + make it easy to switch back to lax. + + Larry + +Do you copy? As of Perl 5.8.7, B<UTF-8> means strict, official UTF-8 +while B<utf8> means liberal, lax, version thereof. And Encode version +2.10 or later thus groks the difference between C<UTF-8> and C"utf8". + + encode("utf8", "\x{FFFF_FFFF}", 1); # okay + encode("UTF-8", "\x{FFFF_FFFF}", 1); # croaks + +C<UTF-8> in Encode is actually a canonical name for C<utf-8-strict>. +Yes, the hyphen between "UTF" and "8" is important. Without it Encode +goes "liberal" + + find_encoding("UTF-8")->name # is 'utf-8-strict' + find_encoding("utf-8")->name # ditto. names are case insensitive + find_encoding("utf8")->name # ditto. "_" are treated as "-" + find_encoding("UTF8")->name # is 'utf8'. + + +=head1 SEE ALSO + +L<Encode::Encoding>, +L<Encode::Supported>, +L<Encode::PerlIO>, +L<encoding>, +L<perlebcdic>, +L<perlfunc/open>, +L<perlunicode>, +L<utf8>, +the Perl Unicode Mailing List E<lt>perl-unicode@perl.orgE<gt> + +=head1 MAINTAINER + +This project was originated by Nick Ing-Simmons and later maintained +by Dan Kogai E<lt>dankogai@dan.co.jpE<gt>. See AUTHORS for a full +list of people involved. For any questions, use +E<lt>perl-unicode@perl.orgE<gt> so we can all share. + +=cut |