/usr/lib/swi-prolog/doc/Manual/modules.html

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<H1><A NAME="sec:5"><SPAN class="sec-nr">5</SPAN> <SPAN class="sec-title">Modules</SPAN></A></H1>

<A NAME="sec:modules"></A>

<P>A Prolog module is a collection of predicates which defines a public 
interface by means of a set of provided predicates and operators. Prolog 
modules are defined by an ISO standard. Unfortunately, the standard is 
considered a failure and, as far as we are aware, not implemented by any 
concrete Prolog implementation. The SWI-Prolog module system is derived 
from the Quintus Prolog module system. The Quintus module system has 
been the starting points for the module systems of a number of 
mainstream Prolog systems, such as SICStus, Ciao and YAP.

<P>This chapter motivates and describes the SWI-Prolog module system. 
Novices can start using the module system after reading
<A class="sec" href="defmodule.html">section 5.2</A> and <A class="sec" href="import.html">section 
5.3</A>. The primitives defined in these sections suffice for basic 
usage until one needs to export predicates that call or manage other 
predicates dynamically (e.g., use <A NAME="idx:call1:1221"></A><A class="pred" href="metacall.html#call/1">call/1</A>,
<A NAME="idx:assert1:1222"></A><A class="pred" href="db.html#assert/1">assert/1</A>, 
etc.). Such predicates are called <EM>meta predicates</EM> and are 
discussed in <A class="sec" href="metapred.html">section 5.4</A>. <A class="sec" href="overrule.html">Section 
5.5</A> to <A class="sec" href="moduleop.html">section 5.8</A> describe 
more advanced issues. Starting with <A class="sec" href="importmodule.html">section 
5.9</A>, we discuss more low-level aspects of the SWI-Prolog module 
systems that are used to implement the visible module system, and can be 
used to build other code reuse mechanisms.

<P>
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<H2>Section Index</H2>

</CENTER>
<HR>
<DIV class="toc">
<DIV class="toc-h2"><A class="sec" href="whymodules.html"><SPAN class="sec-nr">5.1</SPAN> <SPAN class="sec-title">Why 
Using Modules?</SPAN></A></DIV>
<DIV class="toc-h2"><A class="sec" href="defmodule.html"><SPAN class="sec-nr">5.2</SPAN> <SPAN class="sec-title">Defining 
a Module</SPAN></A></DIV>
<DIV class="toc-h2"><A class="sec" href="import.html"><SPAN class="sec-nr">5.3</SPAN> <SPAN class="sec-title">Importing 
Predicates into a Module</SPAN></A></DIV>
<DIV class="toc-h2"><A class="sec" href="metapred.html"><SPAN class="sec-nr">5.4</SPAN> <SPAN class="sec-title">Defining 
a meta-predicate</SPAN></A></DIV>
<DIV class="toc-h2"><A class="sec" href="overrule.html"><SPAN class="sec-nr">5.5</SPAN> <SPAN class="sec-title">Overruling 
Module Boundaries</SPAN></A></DIV>
<DIV class="toc-h2"><A class="sec" href="mtoplevel.html"><SPAN class="sec-nr">5.6</SPAN> <SPAN class="sec-title">Interacting 
with modules from the toplevel</SPAN></A></DIV>
<DIV class="toc-h2"><A class="sec" href="reexport.html"><SPAN class="sec-nr">5.7</SPAN> <SPAN class="sec-title">Composing 
modules from other modules</SPAN></A></DIV>
<DIV class="toc-h2"><A class="sec" href="moduleop.html"><SPAN class="sec-nr">5.8</SPAN> <SPAN class="sec-title">Operators 
and modules</SPAN></A></DIV>
<DIV class="toc-h2"><A class="sec" href="importmodule.html"><SPAN class="sec-nr">5.9</SPAN> <SPAN class="sec-title">Dynamic 
importing using import modules</SPAN></A></DIV>
<DIV class="toc-h2"><A class="sec" href="resmodules.html"><SPAN class="sec-nr">5.10</SPAN> <SPAN class="sec-title">Reserved 
Modules and using the `user' module</SPAN></A></DIV>
<DIV class="toc-h2"><A class="sec" href="sec-5.11.html"><SPAN class="sec-nr">5.11</SPAN> <SPAN class="sec-title">An 
alternative import/export interface</SPAN></A></DIV>
<DIV class="toc-h2"><A class="sec" href="dynamic-modules.html"><SPAN class="sec-nr">5.12</SPAN> <SPAN class="sec-title">Dynamic 
Modules</SPAN></A></DIV>
<DIV class="toc-h2"><A class="sec" href="ctxmodule.html"><SPAN class="sec-nr">5.13</SPAN> <SPAN class="sec-title">Transparent 
predicates: definition and context module</SPAN></A></DIV>
<DIV class="toc-h2"><A class="sec" href="manipmodule.html"><SPAN class="sec-nr">5.14</SPAN> <SPAN class="sec-title">Query 
the module system</SPAN></A></DIV>
<DIV class="toc-h2"><A class="sec" href="modulecompat.html"><SPAN class="sec-nr">5.15</SPAN> <SPAN class="sec-title">Compatibility 
of the Module System</SPAN></A></DIV>
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swi-prolog-nox 5.10.4-3ubuntu1 / usr / lib / swi-prolog / doc / Manual / modules.html
