$utf8::hint_bits = 0x00800000;
-our $VERSION = '1.02';
+our $VERSION = '1.06';
sub import {
$^H |= $utf8::hint_bits;
sub AUTOLOAD {
require "utf8_heavy.pl";
goto &$AUTOLOAD if defined &$AUTOLOAD;
+ require Carp;
Carp::croak("Undefined subroutine $AUTOLOAD called");
}
"pragmatic" effect.
Until UTF-8 becomes the default format for source text, either this
-pragma or the L</encoding> pragma should be used to recognize UTF-8
+pragma or the L<encoding> 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<UTF-X> is used to refer to UTF-8 on ASCII and ISO
=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
+as being part of a literal UTF-X sequence. This includes most
literals such as identifier names, string constants, and constant
regular expression patterns.
Note that if you have bytes with the eighth bit on in your script
(for example embedded Latin-1 in your string literals), C<use utf8>
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<no utf8;>.
+UTF-X. If you want to have such bytes under C<use utf8>, you can disable
+this pragma until the end the block (or file, if at top level) by
+C<no utf8;>.
-If you want to automatically upgrade your 8-bit legacy bytes to UTF-8,
-use the L</encoding> pragma instead of this pragma. For example, if
-you want to implicitly upgrade your ISO 8859-1 (Latin-1) bytes to UTF-8
+If you want to automatically upgrade your 8-bit legacy bytes to Unicode,
+use the L<encoding> pragma instead of this pragma. For example, if
+you want to implicitly upgrade your ISO 8859-1 (Latin-1) bytes to Unicode
as used in e.g. C<chr()> and C<\x{...}>, try this:
use encoding "latin-1";
my $c = chr(0xc4);
my $x = "\x{c5}";
-In case you are wondering: yes, C<use encoding 'utf8';> works much
-the same as C<use utf8;>.
+In case you are wondering: C<use encoding 'utf8';> is mostly the same as
+C<use utf8;>, except that C<use encoding> marks all string literals in the
+source code as Unicode, regardless of whether they contain any high-bit bytes.
+Moreover, C<use encoding> installs IO layers on C<STDIN> and C<STDOUT> to work
+with Unicode strings; see L<encoding> for details.
=head2 Utility functions
=item * $num_octets = utf8::upgrade($string)
-Converts (in-place) internal representation of string to Perl's
-internal I<UTF-X> form. Returns the number of octets necessary to
-represent the string as I<UTF-X>. Can be used to make sure that the
-UTF-8 flag is on, so that C<\w> or C<lc()> work as expected on strings
-containing characters in the range 0x80-0xFF (oon ASCII and
-derivatives). Note that this should not be used to convert a legacy
-byte encoding to Unicode: use Encode for that. Affected by the
-encoding pragma.
+Converts in-place the octet sequence in the native encoding
+(Latin-1 or EBCDIC) to the equivalent character sequence in I<UTF-X>.
+I<$string> already encoded as characters does no harm.
+Returns the number of octets necessary to represent the string as I<UTF-X>.
+Can be used to make sure that the UTF-8 flag is on,
+so that C<\w> or C<lc()> work as Unicode on strings
+containing characters in the range 0x80-0xFF (on ASCII and
+derivatives).
+
+B<Note that this function does not handle arbitrary encodings.>
+Therefore I<Encode.pm> is recommended for the general purposes.
+
+Affected by the encoding pragma.
=item * $success = utf8::downgrade($string[, FAIL_OK])
-Converts (in-place) internal representation of string to be un-encoded
-bytes. Returns true on success. On failure dies or, if the value of
-FAIL_OK is true, returns false. Can be used to make sure that the
-UTF-8 flag is off, e.g. when you want to make sure that the substr()
-or length() function works with the usually faster byte algorithm.
-Note that this should not be used to convert Unicode back to a legacy
-byte encoding: use Encode for that. B<Not> affected by the encoding
-pragma.
+Converts in-place the character sequence in I<UTF-X>
+to the equivalent octet sequence in the native encoding (Latin-1 or EBCDIC).
+I<$string> already encoded as octets does no harm.
+Returns true on success. On failure dies or, if the value of
+C<FAIL_OK> is true, returns false.
+Can be used to make sure that the UTF-8 flag is off,
+e.g. when you want to make sure that the substr() or length() function
+works with the usually faster byte algorithm.
+
+B<Note that this function does not handle arbitrary encodings.>
+Therefore I<Encode.pm> is recommended for the general purposes.
+
+B<Not> affected by the encoding pragma.
+
+B<NOTE:> this function is experimental and may change
+or be removed without notice.
=item * utf8::encode($string)
-Converts in-place the octets of the I<$string> to the octet sequence
-in Perl's I<UTF-X> encoding. Returns nothing. B<Note that this does
-not change the "type" of I<$string> to UTF-8>, and that this handles
-only ISO 8859-1 (or EBCDIC) as the source character set. Therefore
-this should not be used to convert a legacy 8-bit encoding to Unicode:
-use Encode::decode() for that. In the very limited case of wanting to
-handle just ISO 8859-1 (or EBCDIC), you could use utf8::upgrade().
+Converts in-place the character sequence to the corresponding octet sequence
+in I<UTF-X>. The UTF-8 flag is turned off. Returns nothing.
+
+B<Note that this function does not handle arbitrary encodings.>
+Therefore I<Encode.pm> is recommended for the general purposes.
=item * utf8::decode($string)
-Attempts to convert I<$string> in-place from Perl's I<UTF-X> encoding
-into octets. Returns nothing. B<Note that this does not change the
-"type" of <$string> from UTF-8>, and that this handles only ISO 8859-1
-(or EBCDIC) as the destination character set. Therefore this should
-not be used to convert Unicode back to a legacy 8-bit encoding:
-use Encode::encode() for that. In the very limited case of wanting
-to handle just ISO 8859-1 (or EBCDIC), you could use utf8::downgrade().
+Attempts to convert in-place the octet sequence in I<UTF-X>
+to the corresponding character sequence. The UTF-8 flag is turned on
+only if the source string contains multiple-byte I<UTF-X> characters.
+If I<$string> is invalid as I<UTF-X>, returns false; otherwise returns true.
+
+B<Note that this function does not handle arbitrary encodings.>
+Therefore I<Encode.pm> is recommended for the general purposes.
+
+B<NOTE:> this function is experimental and may change
+or be removed without notice.
=item * $flag = utf8::is_utf8(STRING)
https://perl5.git.perl.org / perl5.git / blobdiff