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package utf8;
$utf8::hint_bits = 0x00800000;
our $VERSION = '1.00';
sub import {
$^H |= $utf8::hint_bits;
$enc{caller()} = $_[1] if $_[1];
}
sub unimport {
$^H &= ~$utf8::hint_bits;
}
sub AUTOLOAD {
require "utf8_heavy.pl";
goto &$AUTOLOAD if defined &$AUTOLOAD;
Carp::croak("Undefined subroutine $AUTOLOAD called");
}
1;
__END__
=head1 NAME
utf8 - Perl pragma to enable/disable UTF-8 (or UTF-EBCDIC) in source code
=head1 SYNOPSIS
use utf8;
no utf8;
=head1 DESCRIPTION
WARNING: The implementation of Unicode support in Perl is incomplete.
See L<perlunicode> for the exact details.
The C<use utf8> pragma tells the Perl parser to allow UTF-8 in the
program text in the current lexical scope (allow UTF-EBCDIC on EBCDIC based
platforms). The C<no utf8> pragma tells Perl to switch back to treating
the source text as literal bytes in the current lexical scope.
This pragma is primarily a compatibility device. Perl versions
earlier than 5.6 allowed arbitrary bytes in source code, whereas
in future we would like to standardize on the UTF-8 encoding for
source text. Until UTF-8 becomes the default format for source
text, this pragma should be used to recognize UTF-8 in the source.
When UTF-8 becomes the standard source format, this pragma will
effectively become a no-op. For convenience in what follows the
term UTF-X is used to refer to UTF-8 on ASCII and ISO Latin based
platforms and UTF-EBCDIC on EBCDIC based platforms.
Enabling the C<utf8> pragma has the following effects:
=over 4
=item *
Bytes in the source text that have their high-bit set will be treated
as being part of a literal UTF-8 character. This includes most literals
such as identifiers, string constants, constant regular expression patterns
and package names. On EBCDIC platforms characters in the Latin 1
character set are treated as being part of a literal UTF-EBCDIC character.
=item *
In the absence of inputs marked as UTF-X, regular expressions within the
scope of this pragma will default to using character semantics instead
of byte semantics.
@bytes_or_chars = split //, $data; # may split to bytes if data
# $data isn't UTF-X
{
use utf8; # force char semantics
@chars = split //, $data; # splits characters
}
=back
=head2 Utility functions
The following functions are defined in the C<utf8::> package by the perl core.
=over 4
=item * $num_octets = utf8::upgrade($string);
Converts internal representation of string to the perls internal UTF-X form.
Returns the number of octets necessary to represent the string as UTF-X.
=item * utf8::downgrade($string[, CHECK])
Converts internal representation of string to be un-encoded bytes.
=item * utf8::encode($string)
Converts (in-place) I<$string> from logical characters to octet sequence
representing it in perl's UTF-X encoding.
=item * $flag = utf8::decode($string)
Attempts to convert I<$string> in-place from perl's UTF-X encoding into logical characters.
=back
=head1 SEE ALSO
L<perlunicode>, L<bytes>
=cut
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