5.3.14. Relation Class

A Relation is a MapCollection with indexes that can be any object. In a Relation, each item is associated with a single index, but there can be more than one item with the same index (unlike a Table, which can contain only one item for any index).

Table 5.24. Relation Class

Object

Methods inherited from the Object class

Class (Metaclass)

Methods inherited from the Class class

+ Collection (Mixin Class)

Methods inherited from the Collection class

[] (Abstract Method)	equivalent	put (Abstract Method)
[]= (Abstract Method)	hasIndex	subset
allIndexes (Abstract Method)	hasItem	supplier
allItems (Abstract Method)	index (Abstract Method)	union
at (Abstract Method)	intersection	xor
difference	items
disjoint	makeArray

+ MapCollection (Mixin Class)

Methods inherited from the MapCollection class

Relation

[]	hasIndex	removeAll
[]=	hasItem	removeItem
allAt	index	subset
allIndex	intersection	supplier
allIndexes	isEmpty	union
allItems	items	uniqueIndexes
at	makeArray	xor
difference	put
empty	remove