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Alt-0.19
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/ Alt::Assert

NAME

Alt::Assert - Assert alternate module implementation

SYNOPSIS

Assuming there is a CPAN module Foo::Bar and mst wants to write an ALTernate called Alt::Foo::Bar::MSTROUT.

In mst's Foo::Bar, there is the following line:

use constant ALT => 'MSTROUT';

In the alt module:

package Alt::Foo::Bar::MSTROUT;
use Alt::Assert; # imports assert()
1;

Users use mst's Foo::Bar as normal, just like they would use the original Foo::Bar:

use Foo::Bar -various => [qw(weird import)], {API=>'things'};

or:

require Foo::Bar;

If they want to assert they have the mst version, they can:

use Foo::Bar -various => [qw(weird import)], {API=>'things'};
use Alt::Foo::Bar::MSTROUT;

or:

require Foo::Bar;
require Alt::Foo::Bar::MSTROUT;
Alt::Foo::Bar::MSTROUT->assert;

DESCRIPTION

Alt::Assert can be used to assert that the loaded module is the wanted alternate implementation. Using the Synopsis' example, there can be different Foo::Bar installed, either from the original distribution, or from one of the alternate ones. Each alternate might be slightly incompatible with the original. The existence of Alt::Foo::Bar::MSTROUT in the installation does not necessarily ensure that the installed Foo::Bar is from the same alternate distribution, since an installer can replace Foo::Bar from another distribution. That is why one might need to do this assertion.

SEE ALSO

AUTHOR

Ingy döt Net <ingy@cpan.org>

COPYRIGHT

Copyright 2012-2014. Ingy döt Net.

See http://www.perl.com/perl/misc/Artistic.html