Chapter 2 Building an XML model
Managing external shortcuts through references and data types
  | External shortcuts allow you to share objects between different models. You  | 
  | can define external shortcuts in an XML model, but you cannot use them  | 
  | directly in the model, except as substitution groups for elements (see Detail  | 
  | page in element property sheet).  | 
  | You can define external shortcuts for any global object (with no parent object  | 
  | in the diagram), except for imports, includes, redefines and annotations.  | 
  | Internal shortcuts allow you to share objects between packages of a same  | 
  | model. You cannot define internal shortcuts since an XML model does not  | 
  | support packages.  | 
  | External shortcuts are automatically generated in the following situations:  | 
References | When you use the Reference property to define an element, an attribute, a  | 
  | group or an attribute group, by reference to a similar object in another model  | 
  | opened in the workspace, a shortcut is created between the referencing object  | 
  | and the target object.  | 
  | The shortcut appears in the current model with a specific item in the Browser  | 
  | tree view and the “(Shortcut)” expression in the reference symbol and item.  | 
  | The target object keeps track of the referencing object in the Reference tab of  | 
  | the Dependencies page of its property sheet.  | 
Data types | When you define the data type of an element by selecting a simple or a  | 
  | complex type from another model (using the Browse tool beside the Type  | 
  | dropdown listbox), a shortcut is created between the current element type and  | 
  | the target data type.  | 
  | The shortcut appears in the current model with a specific item in the Browser  | 
  | tree view.  | 
XSM User's Guide  | 87  |