4.27.5 reference and shared operations

All operations of the underlying objects are forwarded by reference and shared objects. THis kind of dereferencing is done automatically in most cases:

Example:

In some cases references have to be dereferenced explicitely. For instance, this is the case for n-ary function calls not starting with a reference or shared object. You can use the link operator or a type cast to work around this. In contrast, some constructs like left-hand subexpressions prematurely evaluate. You can avoid this by using the def operator or by explicitly type casting to reference.

In particular, explicit dereferencing is useful to distinguish between typecasting and nested constructings.