NAME
Encode::Alias - alias defintions to encodings
SYNOPSIS
use Encode;
use Encode::Alias;
define_alias( newName => ENCODING);
DESCRIPTION
Allows newName to be used as am alias for ENCODING. ENCODING may be either the name of an encoding or and encoding object (as described in Encode).
Currently newName can be specified in the following ways:
- As a simple string.
- As a qr// compiled regular expression, e.g.:
-
define_alias( qr/^iso8859-(\d+)$/i => '"iso-8859-$1"' );
In this case if ENCODING is not a reference it is
eval
-ed to allow$1
etc. to be subsituted. The example is one way to names as used in X11 font names to alias the MIME names for the iso-8859-* family. Note the double quote inside the single quote.If you are using regex here, you have to do so or it won't work in this case. Also not regex is tricky even for the experienced. Use it with caution.
- As a code reference, e.g.:
-
define_alias( sub { return /^iso8859-(\d+)$/i ? "iso-8859-$1" : undef } , '');
In this case
$_
will be set to the name that is being looked up and ENCODING is passed to the sub as its first argument. The example is another way to names as used in X11 font names to alias the MIME names for the iso-8859-* family.
Alias overloading
You can override predefined aliases by simply applying define_alias(). New alias is always evaluated first and when neccessary define_alias() flushes internal cache to make new definition available.
# redirect SHIFT_JIS to MS/IBM Code Page 932, which is a
# superset of SHIFT_JIS
define_alias( qr/shift.*jis$/i => '"cp932"' );
define_alias( qr/sjis$/i => '"cp932"' );
If you want to zap all predefined aliases, you can
Encode::Alias->undef_aliases;
to do so. And
Encode::Alias->init_aliases;
gets factory setting back.