dpans/concept-reinit.tex

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The generic function \funref{reinitialize-instance} may be used to change
the values of \term{slots} according to initialization arguments.

The process of reinitialization changes the values of some \term{slots} and
performs any user-defined actions.  It does not modify the structure
of an \term{instance} to add or delete \term{slots}, 
and it does not use any \kwd{initform} forms to initialize \term{slots}.

The generic function \funref{reinitialize-instance} may be called
directly.  It takes one required argument, the \term{instance}.  It also
takes any number of initialization arguments to be used by \term{methods} for
\funref{reinitialize-instance} or for \funref{shared-initialize}. The
arguments after the required \term{instance} must form an 
\term{initialization argument list}.
                                               
There is a system-supplied primary \term{method} for 
\funref{reinitialize-instance} whose \term{parameter specializer} is 
\theclass{standard-object}.  First this \term{method} checks the validity of
initialization arguments and signals an error if an initialization
argument is supplied that is not declared as valid. 
(For more information, \seesection\DeclaringInitargValidity.)
Then it calls the generic function 
\funref{shared-initialize} with the following arguments: the \term{instance},
\nil, and the initialization arguments it received.

\beginsubsection{Customizing Reinitialization}             

\term{Methods} for \funref{reinitialize-instance} may be defined to specify
actions to be taken when an \term{instance} is updated.  If only
\term{after methods} for \funref{reinitialize-instance} are defined, 
they will be run after the system-supplied primary \term{method} for 
initialization and therefore will not interfere with the default behavior of 
\funref{reinitialize-instance}.

\term{Methods} for \funref{shared-initialize} may be defined to customize 
\term{class} redefinition.  For more information, \seesection\SharedInitialize.

\endsubsection%{Customizing Reinitialization}