Define a class-variable for the given class. Name is the name of
the class-variable. If this name matches the name of an instance
variable (see class variable),
the class-variable will be used as a default for the instance variable. Default
defines the value if no value is specified in the Defaults file (see pce->load_defaults). Type
declares the type. If the class-variable acts as a default-variable for
an instance-variable, using @default
will copy the type of the instance-variable. Summary is used for
documentation. When absent, the documentation from the corresponding
instance variable is used, or the documentation from a class-variable
defined in one of the super-classes.
Class-variables are normally defined using class_variable/4
in the definition of a user-defined class.
