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<b>Common Lisp the Language, 2nd Edition</b>
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<H3><A NAME=SECTION003218200000000000000>28.1.8.2. Standard Metaclasses</A></H3>
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The Common Lisp Object System provides a number of predefined metaclasses. These include the
classes <tt>standard-class</tt>, <tt>built-in-class</tt>, and
<tt>structure-class</tt>:
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The class <tt>standard-class</tt> is the default class of classes defined
by <tt>defclass</tt>.
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<LI> The class <tt>built-in-class</tt> is the class whose
instances are classes that have special implementations with
restricted capabilities. Any class that corresponds to a standard
Common Lisp type
might be an instance of <tt>built-in-class</tt>.
The predefined Common Lisp type specifiers that are required to have
corresponding classes are listed in table <A HREF="node273.html#CLOSPRECEDENCETABLE">28-1</A>.
It is implementation-dependent whether each of these classes is implemented as a built-in class.
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All classes defined by means of <tt>defstruct</tt> are instances of
<tt>structure-class</tt>.
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