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

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<H2><A NAME="sec:B.6"><SPAN class="sec-nr">B.6</SPAN> <SPAN class="sec-title">Hooks 
for loading files</SPAN></A></H2>

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

<P>All loading of source-files is achieved by <A NAME="idx:loadfiles2:1677"></A><A class="pred" href="consulting.html#load_files/2">load_files/2</A>. 
The hook
<A NAME="idx:prologloadfile2:1678"></A><A class="pred" href="loadfilehook.html#prolog_load_file/2">prolog_load_file/2</A> 
can be used to load Prolog code from non-files or even load entirely 
different information, such as foreign files.

<DL class="latex">
<DT class="pubdef"><A NAME="prolog_load_file/2"><STRONG>prolog_load_file</STRONG>(<VAR>+Spec, 
+Options</VAR>)</A></DT>
<DD class="defbody">
Load a single object. If this call succeeds, <A NAME="idx:loadfiles2:1679"></A><A class="pred" href="consulting.html#load_files/2">load_files/2</A> 
assumes the action has been taken care of. This hook is only called if <VAR>Options</VAR> 
does not contain the <CODE>stream(Input)</CODE> option. The hook must be 
defined in the module <CODE>user</CODE>.

<P>The <CODE>library(http_load)</CODE> provides an example, loading 
Prolog sources directly from an HTTP server.</DD>
<DT class="pubdef"><A NAME="prolog:comment_hook/3"><STRONG>prolog:comment_hook</STRONG>(<VAR>+Comments, 
+Pos, +Term</VAR>)</A></DT>
<DD class="defbody">
This hook allows for processing ---structured--- comments encountered by 
the compiler. The reader collects all comments found from the current 
position to the end of the next term. It calls this hook providing a 
list of <VAR>Position</VAR>-<VAR>Comment</VAR> in <VAR>Comments</VAR>, 
the start-position of the next term in <VAR>Pos</VAR> and the next term 
itself in <VAR>Term</VAR>. All positions are stream-position terms. This 
hook is exploited by the documentation system. See
<A NAME="idx:streampositiondata3:1680"></A><A class="pred" href="IO.html#stream_position_data/3">stream_position_data/3</A>. 
See also <A NAME="idx:readterm3:1681"></A><A class="pred" href="termrw.html#read_term/3">read_term/3</A>.
</DD>
</DL>

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swi-prolog-nox 5.10.4-3ubuntu1 / usr / lib / swi-prolog / doc / Manual / loadfilehook.html
