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The UML diagram below shows the introduction of the SequenceChild class in the Gram object tree, and how it relates to the runtime classes derived from SequenceChildParser and SequenceChildUnparser.
This is the primary architectural change in this proposed refactoring. A sequence parser, for example, is a loop that drives a number of sequence child parsers, some of which are for scalars (elements or model groups that are not repeating/optional), others are for array/optional elements.
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