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 The C 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 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 I is used to refer to UTF-8 on ASCII and ISO Latin based platforms and UTF-EBCDIC on EBCDIC based platforms. Enabling the C pragma has the following effect: =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. =back Note that if you have bytes with the eighth bit on in your script (for example embedded Latin-1 in your string literals), C will be unhappy since the bytes are most probably not well-formed UTF-8. If you want to have such bytes and use utf8, you can disable utf8 until the end the block (or file, if at top level) by C. =head2 Utility functions The following functions are defined in the C package by the perl core. =over 4 =item * $num_octets = utf8::upgrade($string); Converts internal representation of string to the Perl's internal I form. Returns the number of octets necessary to represent the string as I. Note that this should not be used to convert a legacy byte encoding to Unicode: use Encode for that. Affected by the encoding pragma. =item * utf8::downgrade($string[, CHECK]) Converts internal representation of string to be un-encoded bytes. Note that this should not be used to convert Unicode back to a legacy byte encoding: use Encode for that. B affected by the encoding pragma. =item * utf8::encode($string) Converts (in-place) I<$string> from logical characters to octet sequence representing it in Perl's I encoding. Note that this should not be used to convert a legacy byte encoding to Unicode: use Encode for that. =item * $flag = utf8::decode($string) Attempts to convert I<$string> in-place from Perl's I encoding into logical characters. Note that this should not be used to convert Unicode back to a legacy byte encoding: use Encode for that. =item * $flag = utf8::valid(STRING) [INTERNAL] Test whether STRING is in a consistent state. Will return true if string is held as bytes, or is well-formed UTF-8 and has the UTF-8 flag on. Main reason for this routine is to allow Perl's testsuite to check that operations have left strings in a consistent state. =back C is like C, but the UTF8 flag is cleared. See L for more on the UTF8 flag and the C API functions C, C, C, and C, which are wrapped by the Perl functions C, C, C and C. =head1 SEE ALSO L, L =cut