/// <summary>
/// Register a named collection. A collection is identified by a URI (the collection URI),
/// and its content is represented by an <c>IEnumerable</c> that enumerates the contents
/// of the collection. The values delivered by this enumeration are Uri values, which
/// can be mapped to nodes using the registered <c>XmlResolver</c>.
/// </summary>
/// <param name="collectionUri">The URI used to identify the collection in a call
/// of the XPath <c>collection()</c> function. The default collection is registered
/// by supplying null as the value of this argument (this is the collection returned
/// when the XPath <c>collection()</c> function is called with no arguments).</param>
/// <param name="contents">An enumerable object that represents the contents of the
/// collection, as a sequence of document URIs. The enumerator returned by this
/// IEnumerable object must return instances of the Uri class.</param>
/// <remarks>
/// <para>Collections should be stable: that is, two calls to retrieve the same collection URI
/// should return the same sequence of document URIs. This requirement is imposed by the
/// W3C specifications, but in the case of a user-defined collection it is not enforced by
/// the Saxon product.</para>
/// <para>A collection may be "unregistered" by providing null as the value of the
/// contents argument. A collection may be replaced by specifying the URI of an existing
/// collection.</para>
/// <para>Collections registered with a processor are available to all queries and stylesheets
/// running under the control of that processor. Collections should not normally be registered
/// while queries and transformations are in progress.</para>
/// </remarks>
///
public void RegisterCollection(Uri collectionUri, IEnumerable contents)
{
String u = (collectionUri == null ? null : collectionUri.ToString());
DotNetCollectionURIResolver resolver =
(DotNetCollectionURIResolver)config.getCollectionURIResolver();
resolver.registerCollection(u, contents);
}
