Annex C: Extensible Markup Language (XML)
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Here the parent element contains a sequence of four elements, where clshall appear once, c2 may appear, c3 may appear one or more times, and c4 may appear zero
or more times.
An element with a choice of child elements is declared as follows:









Here the car ---'part element contains a group of elements that has a choice order.
Thus, a car ---'part instance will contain one of the three elements, dOOf, wheel or engine. Also notice the "rer' attribute of the element declaration. This refers to an element that is already defined somewhere else in the schema.
Attributes can also be specified in type definitions.











Here we have defined five attributes for the type point. The "dirn" attribute is of
an enumerated type, where three values are allowed and "twoD" is the default value.
The "z" attribute is optional.