utf8 - Perl pragma to enable/disable UTF-8 in source code

- NAME
- SYNOPSIS
- DESCRIPTION
- SEE ALSO

# NAME

utf8 - Perl pragma to enable/disable UTF-8 in source code

# SYNOPSIS

        use utf8;
        no utf8;

# DESCRIPTION

WARNING: The implementation of Unicode support in Perl is incomplete. See the perlunicode manpage for the exact details.

The `use utf8` pragma tells the Perl parser to allow UTF-8 in the program text in the current lexical scope. The `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. This pragma already is a no-op on EBCDIC platforms (where it is alright to code perl in EBCDIC rather than UTF-8).

Enabling the `utf8` pragma has the following effects:

- 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.

- In the absence of inputs marked as UTF-8, 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-8
          {
              use utf8;                       # force char semantics
              @chars = split //, $data;       # splits characters
          }

# SEE ALSO

the perlunicode manpage, the bytes manpage

utf8 - Perl pragma to enable/disable UTF-8 in source code