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Views and path expressions

If the answer format is defined for a complex view, then path expressions like this.cat2.cat21... for the parts of the complex answer can be defined. An example for use of answer formats for views is given in views.sml.

The reader should note that complex path expressions can only refer to components that were defined as retrieved, computed, or inherited attributes in the view definition. For example, one cannot refer to this.dept.budget in the example view EmpDept in views.sml since it is not a retrieved attribute of the dept component of the view definition EmpDept. The second expression of the answer format EmpDeptFormat uses the builtin external procedure UQ. It removes the quotes `"' from a string. Analogously, a procedure QT can be used to put quotes around a term.



ConceptBase Team