<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> <HTML> <HEAD> <TITLE>Programming in XPCE/Prolog</TITLE><LINK REL=home HREF="index.html"> <LINK REL=contents HREF="Contents.html"> <LINK REL=index HREF="DocIndex.html"> <LINK REL=summary HREF="summary.html"> <LINK REL=previous HREF="sec-5.6.html"> <LINK REL=next HREF="notprolog.html"> <STYLE type="text/css"> /* Style sheet for SWI-Prolog latex2html */ dd.defbody { margin-bottom: 1em; } dt.pubdef { background-color: #c5e1ff; } pre.code { margin-left: 1.5em; margin-right: 1.5em; border: 1px dotted; padding-top: 5px; padding-left: 5px; padding-bottom: 5px; background-color: #f8f8f8; } div.navigate { text-align: center; background-color: #f0f0f0; border: 1px dotted; padding: 5px; } div.title { text-align: center; padding-bottom: 1em; font-size: 200%; font-weight: bold; } div.author { text-align: center; font-style: italic; } div.abstract { margin-top: 2em; background-color: #f0f0f0; border: 1px dotted; padding: 5px; margin-left: 10%; margin-right:10%; } div.abstract-title { text-align: center; padding: 5px; font-size: 120%; font-weight: bold; } div.toc-h1 { font-size: 200%; font-weight: bold; } div.toc-h2 { font-size: 120%; font-weight: bold; margin-left: 2em; } div.toc-h3 { font-size: 100%; font-weight: bold; margin-left: 4em; } div.toc-h4 { font-size: 100%; margin-left: 6em; } span.sec-nr { } span.sec-title { } span.pred-ext { font-weight: bold; } /* Footnotes */ sup.fn { color: blue; text-decoration: underline; } span.fn-text: { display: none; } sup.fn span {display: none;} sup:hover span { display: block !important; position: absolute; top: auto; left: auto; width: 80%; color: #000; background: white; border: 2px solid; padding: 5px; margin: 10px; z-index: 100; font-size: smaller; } </STYLE> </HEAD> <BODY BGCOLOR="white"> <DIV class="navigate"><A class="nav" href="index.html"><IMG SRC="home.gif" BORDER=0 ALT="Home"></A> <A class="nav" href="Contents.html"><IMG SRC="index.gif" BORDER=0 ALT="Contents"></A> <A class="nav" href="DocIndex.html"><IMG SRC="yellow_pages.gif" BORDER=0 ALT="Index"></A> <A class="nav" href="summary.html"><IMG SRC="info.gif" BORDER=0 ALT="Summary"></A> <A class="nav" href="sec-5.6.html"><IMG SRC="prev.gif" BORDER=0 ALT="Previous"></A> <A class="nav" href="notprolog.html"><IMG SRC="next.gif" BORDER=0 ALT="Next"></A> </DIV> <H1><A NAME="sec:6"><SPAN class="sec-nr">6</SPAN> <SPAN class="sec-title">XPCE and Prolog</SPAN></A></H1> <A NAME="sec:pceprolog"></A> <P><font size=-1>XPCE</font> and Prolog are very different systems based on a very different programming paradigm. <font size=-1>XPCE</font> objects have global state and use destructive assignment. <font size=-1>XPCE</font> programming constructs use both procedures (code objects and send-methods) and functions (function objects and get-methods). <font size=-1>XPCE</font> has no notion of non-determinism as Prolog has. <P>The hybrid <font size=-1>XPCE/P</font>rolog environment allows the user to express functionality both in Prolog and in <font size=-1>XPCE</font>. This chapter discusses representation of data and dealing with object-references in <font size=-1>XPCE/P</font>rolog . <P> <HR> <CENTER> <H2>Section Index</H2> </CENTER> <HR> <DIV class="toc"> <DIV class="toc-h2"><A class="sec" href="notprolog.html"><SPAN class="sec-nr">6.1</SPAN> <SPAN class="sec-title">XPCE is not Prolog!</SPAN></A></DIV> <DIV class="toc-h2"><A class="sec" href="prologdata.html"><SPAN class="sec-nr">6.2</SPAN> <SPAN class="sec-title">Dealing with Prolog data</SPAN></A></DIV> <DIV class="toc-h3"><A class="sec" href="prologdata.html#sec:6.2.1"><SPAN class="sec-nr">6.2.1</SPAN> <SPAN class="sec-title">Life-time of Prolog terms in XPCE</SPAN></A></DIV> </DIV> </BODY></HTML>