# Package org.eclipse.viatra.query.patternlanguage.typing

- Interface Summary
  Interface | Description
  --- | ---
  ITypeInferrer | The type inferrer calculates the types of variables and variable references of the pattern model.
  ITypeSystem | A type system represents the types (classes, or references) provided by a modeling backend.

- Class Summary
  Class | Description
  --- | ---
  AbstractTypeInferrer |
  AbstractTypeSystem |
  ITypeInferrer.NullTypeInferrer | An empty implementation of `ITypeInferrer` that can be used by the abstract pattern language module.
  ITypeSystem.NullTypeSystem | An empty implementation of `ITypeSystem` that can be used by the abstract pattern language module.
  PatternLanguageTypeRules |
  TypeInformation | This class is used to store type information for selected patterns