Partition in map rules

When a type is partitioned, its subtypes or partitions appear in the card.

In a map rule, a partition is referenced by the symbol <>.

For example, the partition CallRecord of the group type SetofCallRecords is CallRecord<>SetofCallRecords.

Think of a partition as a particular kind of the partitioned type. For example, in the name Detail<>Record, you can think of it as a Detail kind of Record.

An object name includes component references and partition references. For example, the partition Back of OrderRecord, on the input card File, appears in a map rule as Store Field:CallRecord<>OrderRecord:File