Fixed #21137 -- Documented best practice for URLconfs with repeated pattern prefixes.

In this example, the ``/credit/reports/`` URL will be handled by the

``credit.views.report()`` Django view.

This can be used to remove redundancy from URLconfs where a single pattern

prefix is used repeatedly. For example, consider this URLconf::

    from django.conf.urls import patterns, url

    urlpatterns = patterns('wiki.views',

        url(r'^(?P<page_slug>\w+)-(?P<page_id>\w+)/history/$', 'history'),

        url(r'^(?P<page_slug>\w+)-(?P<page_id>\w+)/edit/$', 'edit'),

        url(r'^(?P<page_slug>\w+)-(?P<page_id>\w+)/discuss/$', 'discuss'),

        url(r'^(?P<page_slug>\w+)-(?P<page_id>\w+)/permissions/$', 'permissions'),

    )

We can improve this by stating the common path prefix only once and grouping

the suffixes that differ::

    from django.conf.urls import include, patterns, url

    urlpatterns = patterns('wiki.views',

        url(r'^(?P<page_slug>\w+)-(?P<page_id>\w+)/', include(patterns('',

            url(r'^history/$', 'history'),

            url(r'^edit/$', 'edit'),

            url(r'^discuss/$', 'discuss'),

            url(r'^permissions/$', 'permissions'),

        ))),

    )

.. _`Django Web site`: https://www.djangoproject.com/

Captured parameters