our %encoding;
my @alias; # ordered matching list
my %alias; # cached known aliases
+ # 0 1 2 3 4 5 6 7 8 9 10
+our @latin2iso_num = ( 0, 1, 2, 3, 4, 9, 10, 13, 14, 15, 16 );
+
sub encodings
{
my $alias = $alias[$i];
my $val = $alias[$i+1];
my $new;
-
if (ref($alias) eq 'Regexp' && $_ =~ $alias)
{
$new = eval $val;
# Allow variants of iso-8859-1 etc.
define_alias( qr/^iso[-_]?(\d+)[-_](\d+)$/i => '"iso-$1-$2"' );
+# At least HP-UX has these.
+define_alias( qr/^iso8859(\d+)$/i => '"iso-8859-$1"' );
+
+# This is a font issue, not an encoding issue.
+# (The currency symbol of the Latin 1 upper half
+# has been redefined as the euro symbol.)
+define_alias( qr/^(.+)\@euro$/i => '"$1"' );
+
# Allow latin-1 style names as well
- # 0 1 2 3 4 5 6 7 8 9 10
-my @latin2iso_num = ( 0, 1, 2, 3, 4, 9, 10, 13, 14, 15, 16 );
-define_alias( qr/^latin[-_]?(\d+)$/i => '"iso-8859-$latin2iso_num[$1]"' );
+define_alias( qr/^(?:iso[-_]?)?latin[-_]?(\d+)$/i => '"iso-8859-$latin2iso_num[$1]"' );
# Common names for non-latin prefered MIME names
define_alias( 'ascii' => 'US-ascii',
'greek' => 'iso-8859-7',
'hebrew' => 'iso-8859-8');
-define_alias( 'ibm-1047' => 'cp1047');
+# At least AIX has IBM-NNN (surprisingly...) instead of cpNNN.
+define_alias( qr/^ibm[-_]?(\d\d\d\d?)$/i => '"cp$1"');
+
+# Standardize on the dashed versions.
+define_alias( qr/^utf8$/i => 'utf-8' );
+define_alias( qr/^koi8r$/i => 'koi8-r' );
+
+# TODO: the HP-UX '8' encodings: arabic8 greek8 hebrew8 roman8 turkish8
+# TODO: the Thai Encoding tis620
+# TODO: the Chinese Encoding gb18030
+# TODO: what is the Japanese 'ujis' encoding seen in some Linuxes?
# Map white space and _ to '-'
define_alias( qr/^(\S+)[\s_]+(.*)$/i => '"$1-$2"' );
{
my ($class,$name) = @_;
my $enc;
+ if (ref($name) && $name->can('new_sequence'))
+ {
+ return $name;
+ }
if (exists $encoding{$name})
{
return $encoding{$name};
Convert B<in-place> the data between two encodings. How did the data
in $string originally get to be in FROM_ENCODING? Either using
-encode() or through PerlIO: See L</"Encode and PerlIO">. For CHECK
+encode() or through PerlIO: See L</"Encoding and IO">. For CHECK
see L</"Handling Malformed Data">.
For example to convert ISO 8859-1 data to UTF-8:
from_to($data, "utf-8", "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.
+
=back
=head2 Handling Malformed Data
=head2 Defining Encodings
- use Encode qw(define_alias);
- define_encoding( $object, 'canonicalName' [,alias...]);
+ use Encode qw(define_alias);
+ define_encoding( $object, 'canonicalName' [,alias...]);
Causes I<canonicalName> to be associated with I<$object>. The object
should provide the interface described in L</"IMPLEMENTATION CLASSES">
C<Encode> provides a "layer" (See L<perliol>) which can transform
data as it is read or written.
- open(my $ilyad,'>:encoding(iso-8859-7)','ilyad.greek');
- print $ilyad @epic;
+Here is how the blind poet would modernise the encoding:
+
+ use Encode;
+ open(my $iliad,'<:encoding(iso-8859-7)','iliad.greek');
+ open(my $utf8,'>:utf8','iliad.utf8');
+ my @epic = <$iliad>;
+ print $utf8 @epic;
+ close($utf8);
+ close($illiad);
In addition the new IO system can also be configured to read/write
UTF-8 encoded characters (as noted above this is efficient):
- open(my $fh,'>:utf8','anything');
- print $fh "Any \x{0021} string \N{SMILEY FACE}\n";
+ open(my $fh,'>:utf8','anything');
+ print $fh "Any \x{0021} string \N{SMILEY FACE}\n";
Either of the above forms of "layer" specifications can be made the default
for a lexical scope with the C<use open ...> pragma. See L<open>.
transform the bytes read from a handle into characters before doing
"character operations" (e.g. C<lc>, C</\W+/>, ...).
-=head1 Encode and PerlIO
-
-The PerlIO layer (new since Perl 5.7) can be used to automatically
-convert the data being read in or written out to be converted from
-some encoding into Perl's internal encoding or from Perl's internal
-encoding into some other encoding.
-
-Examples:
-
- open(my $f, "<:encoding(cp1252)")
-
- open(my $g, ">:encoding(iso-8859-1)")
-
You can also use PerlIO to convert larger amounts of data you don't
want to bring into memory. For example to convert between ISO 8859-1
(Latin 1) and UTF-8 (or UTF-EBCDIC in EBCDIC machines):
- open(F, "<:encoding(iso-8859-1)", "data.txt") or die $!;
- open(G, ">:utf8", "data.utf") or die $!;
- while (<F>) { print G }
+ open(F, "<:encoding(iso-8859-1)", "data.txt") or die $!;
+ open(G, ">:utf8", "data.utf") or die $!;
+ while (<F>) { print G }
+
+ # Could also do "print G <F>" but that would pull
+ # the whole file into memory just to write it out again.
+
+More examples:
- # Could also do "print G <F>" but that would pull
- # the whole file into memory just to write it out again.
+ open(my $f, "<:encoding(cp1252)")
+ open(my $g, ">:encoding(iso-8859-2)")
+ open(my $h, ">:encoding(latin9)") # iso-8859-15
See L<PerlIO> for more information.
https://perl5.git.perl.org / perl5.git / blobdiff