---
name: "DBIx::Class::IntrospectableM2M"
section: "3pm"
platform: "linux"
package: "libdbix-class-introspectablem2m-perl"
version: "0.001002-2"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/DBIx::Class::IntrospectableM2M"
---

# DBIx::Class::IntrospectableM2M(3pm)

Introspect many-to-many shortcuts

## NAME

DBIx::Class::IntrospectableM2M - Introspect many-to-many shortcuts

## SYNOPSIS

In your DBIx::Class Result class (sometimes erroneously referred to as the 'table' class):

```
  __PACKAGE__->load_components(qw/IntrospectableM2M ... Core/);
  #Digest encoder with hex format and SHA-1 algorithm
  __PACKAGE__->many_to_many(roles => user_roles => 'role);
```

When you want to introspect this data

```
   my $metadata = $result_class->_m2m_metadata->{roles};
   #  $metadata->{accessor} method name e.g. 'roles'
   #  $metadata->{relation} maping relation e.g. 'user_roles'
   #  $metadata->{foreign_relation} far-side relation e.g. 'role
   #  $metadata->{attrs}  relationship attributes, if any
   # Convenience methods created by DBIx::Class
   #  $metadata->{rs_method}     'roles_rs'
   #  $metadata->{add_method}    'add_to_roles',
   #  $metadata->{set_method}    'set_roles',
   #  $metadata->{remove_method} 'remove_from_roles'
```

**Note:** The component needs to be loaded *before* Core.

## COMPATIBILITY NOTICE

This module is fairly esoteric and, unless you are dynamically creating something out of a DBIC Schema, is probably the wrong solution for whatever it is you are trying to do. Please be advised that compatibility is not guaranteed for DBIx::Class 0.09000+. We will try to manitain all compatibility, but internal changes might make it impossible.

## DESCRIPTION

Because the many-to-many relationships are not real relationships, they can not be introspected with DBIx::Class. Many-to-many relationships are actually just a collection of convenience methods installed to bridge two relationships. This DBIx::Class component can be used to store all relevant information about these non-relationships so they can later be introspected and examined.

## METHODS

### many\_to\_many

Extended to store all relevant information in the `"_m2m_metadata"` HASH ref.

### \_m2m\_metadata

Accessor to a HASH ref where the keys are the names of m2m relationships and the value is a HASH ref as described in the SYNOPSIS.

## AUTHOR

Guillermo Roditi (groditi) \<groditi@cpan.org\>

## COPYRIGHT AND LICENSE

Copyright (C) 2008 by Guillermo Roditi

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