Equality

Describes a context that provides equality equivalence relation on the set of elements of type Element (or some subdomain). The relation is described by equalsTo function.

Such contexts are used instead of usual equals overloading for several reasons. Some of them are:

• Following structural pattern, any behaviour between elements should not be a part of the elements' logic but a part of assumed context. (For example, summing two integers together, we assume that we are summing them as two integer, but not as a residue of some modulo.)

• Such separation of entities and operations over them brings modularity: you can change operations context leaving the entities the same.