Corresponding C++ library: TG_Db 

When applied to a property it allows type changes requiring a transformation to pass through Schema Evolution and transformations using an ECExpression for any property transform.

Schema: Bentley_Standard_CustomAttributes, Version: 1.13, Class: PropertyTransformationExpression Available properties: "ParserRegularExpression"(string), "TransformationECExpression"(string), "RequiredSymbolSets"(array of string)