The CoSy-fSDL flatform does not contain inheritance information because
domains are flattened.
Because checks the types of rule predicates against the data
model, and performs some type inference, inheritance information is
often lacking.
To support the CoSy-fSDL flatform information, the user may specify
inheritance declarations in the -specification himself.
These declare flatform types (domains and operators) to be more
specific (finer) than others.
In particular this is required, when the type inference algorithm of
infers that two types are non-compatible which are different in
the flatform but were compatible in the original CoSy-fSDL specification.
E.g. consider two domains SimpleSTMT_Assign and
STMT_Assign, where SimpleSTMT is a sub-domain
of STMT.
In the flatform the inheritance relation of SimpleSTMT and
STMT is lost.
If the user specifies FINER SimpleSTMT < STMT;, the type
inference algorithm will know that both types are compatible.
Note that finer types stand to the left.