File: vendor/doctrine/doctrine-cache-bundle/Tests/DependencyInjection/Fixtures/config/xml/custom_providers.xml

<?xml version="1.0" ?>
<srv:container xmlns="http://doctrine-project.org/schemas/symfony-dic/cache"
               xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
               xmlns:srv="http://symfony.com/schema/dic/services"
               xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd
                        http://doctrine-project.org/schemas/symfony-dic/cache http://doctrine-project.org/schemas/symfony-dic/cache/doctrine_cache-1.0.xsd">

    <srv:services>
        <srv:service id="my_custom_provider_service" class="Doctrine\Bundle\DoctrineCacheBundle\Tests\DependencyInjection\Fixtures\Cache\MyCustomType"/>
    </srv:services>

    <doctrine-cache>
        <custom-provider type="my_custom_type">
            <prototype>my_custom_provider_service</prototype>
            <definition-class>Doctrine\Bundle\DoctrineCacheBundle\Tests\DependencyInjection\Fixtures\Definition\MyCustomTypeDefinition</definition-class>
        </custom-provider>

        <custom-provider type="my_custom_type2">
            <prototype>my_custom_provider_service</prototype>
        </custom-provider>

        <provider name="my_custom_type_provider">
             <my_custom_type>
                 <config-foo>foo</config-foo>
                 <config-bar>bar</config-bar>
             </my_custom_type>
         </provider>

         <provider name="my_custom_type_provider2">
             <my_custom_type2>
                 <config-foobar>foobar</config-foobar>
             </my_custom_type2>
         </provider>
    </doctrine-cache>

</srv:container>