X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2Futf8.pm;h=b18a043f10d31fd4e7eec31b42d16e313c4b4375;hb=13a6c0e08df522ae430c77e8a15932642751b605;hp=402127aa59bf23f25d3f3a5e91e4103e6e774fa8;hpb=b3419ed8e52ed491b665f8ffe8367e7a3ced7c6e;p=p5sagit%2Fp5-mst-13.2.git diff --git a/lib/utf8.pm b/lib/utf8.pm index 402127a..b18a043 100644 --- a/lib/utf8.pm +++ b/lib/utf8.pm @@ -1,6 +1,5 @@ package utf8; - $utf8::hint_bits = 0x00800000; our $VERSION = '1.00'; @@ -34,9 +33,6 @@ utf8 - Perl pragma to enable/disable UTF-8 (or UTF-EBCDIC) in source code =head1 DESCRIPTION -WARNING: The implementation of Unicode support in Perl is incomplete. -See L for the exact details. - 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 @@ -49,37 +45,30 @@ 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 +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 effects: +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 C1 control group -and the Latin 1 character set are treated as being part of a literal +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 +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. @@ -88,24 +77,39 @@ The following functions are defined in the C package by the perl core. =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. +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<$string> from logical characters to octet sequence -representing it in perl's UTF-X encoding. +Converts (in-place) I<$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) -=item * $flag = utf8::decode($string) - -Attempts to convert I<$string> in-place from perl's UTF-X encoding into logical characters. +Attempts to convert I<$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. =back +C is like C but the UTF8 flag does not +get turned on. See L for more on the UTF8 flag and the C +API functions C, C, +C, C that are wrapped by the Perl +functions C, C, C and +C. + =head1 SEE ALSO L, L