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<H2><A NAME="sec:8.1"><SPAN class="sec-nr">8.1</SPAN> <SPAN class="sec-title">Accessing
Class Variables</SPAN></A></H2>
<A NAME="sec:classvaraccess"></A>
<P>Class variables define <EM>get-</EM>behaviour and can be accessed
using the normal <A NAME="idx:get313:265"></A><A class="pred" href="sec-D.1.html#get/3">get/[3-13]</A>
call. Class variables are the last type of behaviour checked when
resolving a get-method. Below are the most commonly used methods to
access class-variables.
<DL>
<DT><STRONG>object <-class_variable_value:</STRONG> <VAR>name</VAR></DT>
<DD class="defbody">
any Return the value of the named class-variable. Fails silently if the
class does not define the given class-variable.
</DD>
<DT><STRONG>class <-class_variable:</STRONG> <VAR>name</VAR></DT>
<DD class="defbody">
class_variable Return the <A class="" href="summary.html#class:class_variable">class_variable</A>
object with the given name. Fails silently if the class does not define
the given class-variable.
</DD>
<DT><STRONG>class_variable <->value:</STRONG> <VAR>any</VAR></DT>
<DD class="defbody">
Reads or writes the class-variable value. The argument is type-checked
using <A NAME="idx:classvariablegettype:266"></A>`<B>class_variable<CODE><-</CODE>type</B>'
if the value is written. Writing class-variables should be handled with
care, as existing instances of the class are not notified of the change,
and may not be prepared deal with changes of the class-variable value. <A NAME="idx:pceimagedirectory1:267"></A><SPAN class="pred-ext">pce_image_directory/1</SPAN>
is an example of a predicate modifying the image.path class-variable.
</DD>
</DL>
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