---
name: "Alt::Assert"
section: "3pm"
platform: "linux"
package: "libalt-perl"
version: "0.19-4"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/Alt::Assert"
---

# Alt::Assert(3pm)

Assert alternate module implementation

## 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

- •

  Alt

## AUTHOR

Ingy döt Net \<ingy@cpan.org\>

## COPYRIGHT

Copyright 2012-2014. Ingy döt Net.

See \<http://www.perl.com/perl/misc/Artistic.html\>