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+<TITLE>DEFGENERIC / DEFMETHOD</TITLE>
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+<OBJECT TYPE="application/x-oleobject" CLASSID="clsid:1e2a7bd0-dab9-11d0-b93a-00c04fc99f9e">
+	<PARAM NAME="Keyword" VALUE="DEFGENERIC">
+	<PARAM NAME="Keyword" VALUE="DEFMETHOD">
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+<H1><A NAME="defgeneric"></A>DEFGENERIC / DEFMETHOD</H1>
+<P></P>
+<P>With the defgeneric/defmethod constructs, new generic functions may be written </P>
+<P>directly in CLIPS.  Generic functions are similar to deffunctions because </P>
+<P>they can be used to define new procedural code directly in CLIPS, and they can </P>
+<P>be called like any other function. However, generic functions are much more </P>
+<P>powerful because they can do different things depending on the types </P>
+<P>(or classes) and number of their arguments. For example, a '+' operator could </P>
+<P>be defined which performs concatenation for strings but still performs </P>
+<P>arithmetic addition for numbers.  Generic functions are comprised of </P>
+<P>multiple components called methods, where each method handles different </P>
+<P>cases of arguments for the generic function.  A generic function which has </P>
+<P>more than one method is said to be overloaded.</P>
+<P>A generic function is comprised of a header (similar to a forward declaration) </P>
+<P>and zero or more methods.  A generic function header can either be explicitly </P>
+<P>declared by the user or implicitly declared by the definition of at least one </P>
+<P>method. The defgeneric construct is used to specify the generic function header,</P>
+<P>and the defmethod construct is used for each of the generic function's methods.</P>
+<P>The syntax of the defgeneric/defmethod constructs is:</P>
+<PRE><CODE>(defgeneric &lt;name&gt; [&lt;comment&gt;])
+(defmethod &lt;name&gt; [&lt;index&gt;] [&lt;comment&gt;]
+    (&lt;parameter-restriction&gt;* [&lt;wildcard-parameter&gt;])
+    &lt;action&gt;*)
+&lt;parameter-restriction&gt; ::= &lt;single-field-variable&gt; |
+                            (&lt;single-field-variable&gt; &lt;type&gt;* [&lt;query&gt;])
+&lt;wildcard-parameter&gt;    ::= &lt;multifield-variable&gt;
+&lt;type&gt;                  ::= &lt;class-name&gt;
+&lt;query&gt;                 ::= &lt;global-variable&gt; | &lt;function-call&gt;</CODE></PRE>
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