XML namespace declarations in SP config files

[Peter Schober]

* Matthew X. Economou <xenophon at irtnog.org> [2016-04-06 06:14]:
> Why are there duplicate XML namespace declarations in the SP
> configuration files?  For example, in shibboleth2.xml the top-level
> SPConfig elements sets the default namespace to
> urn:mace:shibboleth:2.0:native:sp:config, but it also sets the conf
> namespace to the same value.  attribute-policy.xml does the same thing,
> where both the default namespace and the basic namespace are set to
> urn:mace:shibboleth:2.0:afp:mf:basic.

The cases where I do this (e.g. in SAML Metadata or the IDP's
attribute-filter.xml) is when I have legacy files using a default
(vs. an explicit) namespace, and have newer rules using an implicit
(vs. a default) namespaces. This way I don't have to rewrite al the
rules only because of (default) namespace (or prefix) changes.
E.g. both <md:EntityDescriptor> and <EntityDescriptor> would validate.
-peter