What is a transformation pattern?

A transformation pattern represents a model fragment (pattern) that occurs in a source model and is to be mapped to a particular model fragment in the target model. Assignments can also be taken into account.

If there is no source model pattern (the left-hand side is blank) but there is a target model pattern, the model fragment must be generated only once in the target model.

Only those things that are permitted in a model are actually modeled, and those that contravene modeling conventions are not.

The transformation pattern consists of the source pattern, the target pattern, and the associated mapping.