/ 
Alias-Any-0.000007
River stage zero No dependents
/ Alias::Any

NAME

Alias::Any - Create lexical aliases under different versions of Perl

VERSION

This document describes Alias::Any version 0.000007

SYNOPSIS

use v5.12;
use Alias::Any;

alias my $scalar_alias = $scalar_var;

alias my @array_alias = @array_var;

alias my %hash_alias = %hash_var;


no Alias::Any;

alias my $var = $ref;    # Syntax error

DESCRIPTION

This module is simply a convenient wrapper around the various mechanisms by which aliases can be defined under different versions of Perl.

Under Perl 5.12 to 5.18, the module uses the 'alias' function from the Data::Alias module to create the requested alias.

But previous releases of Data::Alias didn't work under Perl 5.24 or later, and from Perl 5.22 there is a more robust built-in aliasing mechanism available anyway. So under Perl 5.22 or later, this module uses the built-in mechanism in preference to Data::Alias.

This means you can define simple aliases using a consistent syntax, without needing to worry which version of Perl (or Data::Alias) your code will vebe running under.

INTERFACE

The module exports a single keyword (alias) that constructs the requested alias. The syntax of the keyword is:

alias <new_alias> = <existing_thing>;

The new alias must be a variable (or a variable declaration). The "existing thing" must either be an expression yielding a variable of the same type as the alias (i.e. scalar, array, or hash):

alias $value = $another_value;
alias @list  = @another_list;
alias @data  = @{ get_data_as_array_ref() };

If the alias is a scalar variable the expression can also be a scalar constant:

alias $PI = 3.1415926;

In the latter case, of course, the alias will be immutabe too.

To remove the alias keyword for the rest of the current lexical scope, use:

no Alias::Any;

Note that this only removes the alias keyword; it will have no effect on any aliases already defined at that point.

DIAGNOSTICS

'alias' keyword requires Data::Alias module under Perl %d

Under Perl 5.12 to 5.18, the module uses Data::Alias to implement its magic. You used the module, but it couldn't load Data::Alias.

syntax error at %s, near "alias"

You attempted to declare an alias at a point in the code where the alias keyword was not installed. Did you forget to put a use Alias::Any; earlier in that lexical scope?

Or did you insert a no Alias::Any; somewhere above the alias?

The module may also produce any diagnostic that Data::Alias or Perl's built-in refaliasing does. For example:

use 5.24;
alias my @foo = %bar;
# Dies with: Assigned value is not an ARRAY reference...

CONFIGURATION AND ENVIRONMENT

Alias::Any requires no configuration files or environment variables.

DEPENDENCIES

Keyword::Declare (under Perl 5.22 or later) Data::Alias (under Perl 5.20 or earlier)

INCOMPATIBILITIES

None reported.

BUGS AND LIMITATIONS

The module defines a new alias keyword, so it only works under Perl 5.12 or later.

No bugs have been reported.

Please report any bugs or feature requests to bug-alias-any@rt.cpan.org, or through the web interface at http://rt.cpan.org.

AUTHOR

Damian Conway <DCONWAY@CPAN.org>

LICENCE AND COPYRIGHT

Copyright (c) 2017, Damian Conway <DCONWAY@CPAN.org>. All rights reserved.

This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See perlartistic.

DISCLAIMER OF WARRANTY

BECAUSE THIS SOFTWARE IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE SOFTWARE, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE SOFTWARE "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE SOFTWARE IS WITH YOU. SHOULD THE SOFTWARE PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR, OR CORRECTION.

IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE SOFTWARE AS PERMITTED BY THE ABOVE LICENCE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE SOFTWARE (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE SOFTWARE TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.