/* * Copyright © 2008 World Wide Web Consortium, * * (Massachusetts Institute of Technology, European Research Consortium for * Informatics and Mathematics, Keio University). All Rights Reserved. This * work is distributed under the W3C® Document License [1] in the hope that * it will be useful, but WITHOUT ANY WARRANTY; without even the implied * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. * * [1] http://www.w3.org/Consortium/Legal/2002/copyright-documents-20021231 */ * N.B. the target namespace of this schema document, namely * http://www.w3.org/2008/09/sml, is specified by the 12 * September 2008 working draft of SML (the Service Modeling * Language). That draft, and this namespace, have now been * superseded by later drafts of that specification. The * namespace http://www.w3.org/ns/sml and the schema * document provided at http://www.w3.org/ns/sml-schema.xsd * should be used in preference to this namespace and * this schema document. Specifies if the element contains a reference Specifies that the reference element denotes a “null” reference. To be used only on elements for which sml:ref="true". A qualified name of a global element in the referenced document. If true, requires the target element of the reference to exist in the model. A qualified name of the type of the element in the referenced document. If this attribute is set to true for a type D then instances of D should not create any cycles in a model. More precisely, the directed graph whose edges represent instances of D, and whose nodes represent documents that contain the source or target elements for instances of D, must be acyclic. References in URI scheme must be representend by this element.