4.3.2 Defining Classes
The macro defclass is used to define a new named class.
The definition of a class includes:
- * The name of the new class. For newly-defined classes this name is a proper name.
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- * The list of the direct superclasses of the new class.
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- * A set of slot specifiers. Each slot specifier includes the name of the slot and zero or more slot options. A slot option pertains only to a single slot. If a class definition contains two slot specifiers with the same name, an error is signaled.
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- * A set of class options. Each class option pertains to the class as a whole.
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The slot options and class options of the defclass form provide mechanisms for the following:
- * Supplying a default initial value form for a given slot.
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- * Requesting that methods for generic functions be automatically generated for reading or writing slots.
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- * Controlling whether a given slot is shared by all instances of the class or whether each instance of the class has its own slot.
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- * Supplying a set of initialization arguments and initialization argument defaults to be used in instance creation.
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- * Indicating that the metaclass is to be other than the default. The :metaclass option is reserved for future use; an implementation can be extended to make use of the :metaclass option.
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- * Indicating the expected type for the value stored in the slot.
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- * Indicating the documentation string for the slot.
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