Abstract: To support values of properties, a class includes fields to support values in preallocated memory space and with an option data structure which supports, in instances of the class, references to option values without preallocation of memory space. The field and option values are accessed in an instance object of the class using expressions of the same syntactic form. During compilation, the compiler checks the type of an option value against a type description within the option data structure. If a value has not been set for an instance object, a get operation results in getting of the default value for the class. Different classes may support different forms of data structures such as a linked list or a hash table. During compilation, a method call to an object is encoded without regard to the form of the option data structure. When an option value is changed, a change handler identified by an option binding of the data structure is processed.

Abstract: To support values of properties, a class includes fields to support values in preallocated memory space and with an option data structure which supports, in instances of the class, references to option values without preallocation of memory space. The field and option values are accessed in an instance object of the class using expressions of the same syntactic form. During compilation, the compiler checks the type of an option value against a type description within the option data structure. If a value has not been set for an instance object, a get operation results in getting of the default value for the class. Different classes may support different forms of data structures such as a linked list or a hash table. During compilation, a method call to an object is encoded without regard to the form of the option data structure. When an option value is changed, a change handler identified by an option binding of the data structure is processed.

Abstract: To support values of properties, a class includes fields to support values in preallocated memory space and with an option data structure which supports, in instances of the class, references to option values without preallocation of memory space. The field and option values are accessed in an instance object of the class using expressions of the same syntactic form. During compilation, the compiler checks the type of an option value against a type description within the option data structure. If a value has not been set for an instance object, a get operation results in getting of the default value for the class. Different classes may support different forms of data structures such as a linked list or a hash table. During compilation, a method call to an object is encoded without regard to the form of the option data structure. When an option value is changed, a change handler identified by an option binding of the data structure is processed.

Abstract: To support values of properties, a class includes fields to support values in preallocated memory space and with an option data structure which supports, in instances of the class, references to option values without preallocation of memory space. The field and option values are accessed in an instance object of the class using expressions of the same syntactic form. During compilation, the compiler checks the type of an option value against a type description within the option data structure. If a value has not been set for an instance object, a get operation results in getting of the default value for the class. Different classes may support different forms of data structures such as a linked list or a hash table. During compilation, a method call to an object is encoded without regard to the form of the option data structure. When an option value is changed, a change handler identified by an option binding of the data structure is processed.

Abstract: A system and methods that provide compatibility across multiple versions of a software system, such as an execution engine or run-time system, are disclosed. The software system is structured so that it includes a master module, and one or more helper modules, each helper module being capable of processing applets (i.e., programs or content) that require a particular version of the software system. Each time an applet is to be processed by the software system, the master module determines which helper module should be used to process the applet, and starts the selected helper module if necessary. Compatibility with additional versions can be provided by providing additional helper modules. Because numerous helper modules may be executed simultaneously, applets that require different versions of the software system may be processed simultaneously.

Abstract: To support values of properties, a class includes fields to support values in preallocated memory space and with an option data structure which supports, in instances of the class, references to option values without preallocation of memory space. The field and option values are accessed in an instance object of the class using expressions of the same syntactic form. During compilation, the compiler checks the type of an option value against a type description within the option data structure. If a value has not been set for an instance object, a get operation results in getting of the default value for the class. Different classes may support different forms of data structures such as a linked list or a hash table. During compilation, a method call to an object is encoded without regard to the form of the option data structure. When an option value is changed, a change handler identified by an option binding of the data structure is processed.