<!doctype html public "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> <html> <head> <title>extends_object/2-3</title> <link rel=stylesheet href="../../styles.css" type="text/css"> </head> <body> <hr /> <h2><code><a class="back" title="Return to index" href="../index.html#extends_object2_3">extends_object/2-3</a></code></h2> <hr /> <h4>Description</h4> <blockquote> <pre> extends_object(Prototype, Parent) extends_object(Prototype, Parent, Scope) </pre> <p> Enumerates, by backtracking, all pairs of objects such that the first one extends the second. </p> </blockquote> <h4>Template and modes</h4> <blockquote> <pre> extends_object(?object_identifier, ?object_identifier) extends_object(?object_identifier, ?object_identifier, ?scope) </pre> </blockquote> <h4>Errors</h4> <blockquote> <dl> <dt>Prototype is neither a variable nor a valid object identifier:</dt> <dd><code>type_error(object_identifier, Prototype)</code></dd> <dt>Parent is neither a variable nor a valid object identifier:</dt> <dd><code>type_error(object_identifier, Parent)</code></dd> <dt>Scope is neither a variable nor a valid entity scope:</dt> <dd><code>type_error(scope, Scope)</code></dd> </dl> </blockquote> <h4>Examples</h4> <blockquote> <pre> | ?- extends_object(Object, state_space). | ?- extends_object(Object, list, public). </pre> </blockquote> <hr /> <p class="center"> <strong><a href="abolish_protocol1.html">Previous</a> | <a href="extends_protocol2_3.html">Next</a> | <a href="../index.html">Table of Contents</a> | <a href="../../bibliography.html">Bibliography</a> | <a href="../../glossary.html">Glossary</a></strong> </p> <p class="center"> Last updated on: October 21, 2001 </p> <hr /> </body> </html>