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<a href="#id2610078" class="shortcut">Description</a></nobr></td></tr>
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<a name="redland-heuristics"></a><div class="titlepage"></div>
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<h2>
<a name="id2558068"></a><span class="refentrytitle">Heuristics</span>
</h2>
<p>Heuristics — Utility heuristic functions.</p>
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<div class="refsynopsisdiv">
<h2>Synopsis</h2>
<pre class="synopsis">
char* <a href="redland-heuristics.html#librdf-heuristic-gen-name">librdf_heuristic_gen_name</a> (const char *name);
int <a href="redland-heuristics.html#librdf-heuristic-is-blank-node">librdf_heuristic_is_blank_node</a> (const char *node);
const char* <a href="redland-heuristics.html#librdf-heuristic-get-blank-node">librdf_heuristic_get_blank_node</a> (const char *node);
int <a href="redland-heuristics.html#librdf-heuristic-object-is-literal">librdf_heuristic_object_is_literal</a>
(const char *object);
</pre>
</div>
<div class="refsect1" lang="en">
<a name="id2610078"></a><h2>Description</h2>
<p>
Various utility functions for performing heuristics such as
generating a name, guessing if a string is a URI or RDF literal.
</p>
</div>
<div class="refsect1" lang="en">
<a name="id2610096"></a><h2>Details</h2>
<div class="refsect2" lang="en">
<a name="id2610106"></a><h3>
<a name="librdf-heuristic-gen-name"></a>librdf_heuristic_gen_name ()</h3>
<a class="indexterm" name="id2610118"></a><pre class="programlisting">char* librdf_heuristic_gen_name (const char *name);</pre>
<p>
Generate a new name from an existing name.
</p>
<p>
Adds an integer or increases the integer at the end of the name
in order to generate a new one</p>
<p>
</p>
<div class="variablelist"><table border="0">
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<td><span class="term"><em class="parameter"><code>name</code></em> :</span></td>
<td> the name
</td>
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<tr>
<td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td>
<td> a new name or NULL on failure
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2573950"></a><h3>
<a name="librdf-heuristic-is-blank-node"></a>librdf_heuristic_is_blank_node ()</h3>
<a class="indexterm" name="id2573961"></a><pre class="programlisting">int librdf_heuristic_is_blank_node (const char *node);</pre>
<p>
Try to guess if an node string is a blank node identifier.
</p>
<p>
The guessing is done by assuming the object is a blank node if it matches
^_: like N-Triples, N3 and related.</p>
<p>
</p>
<div class="variablelist"><table border="0">
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<td><span class="term"><em class="parameter"><code>node</code></em> :</span></td>
<td> string object to guess type
</td>
</tr>
<tr>
<td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td>
<td> non 0 if node is probably a blank node identifier
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2574026"></a><h3>
<a name="librdf-heuristic-get-blank-node"></a>librdf_heuristic_get_blank_node ()</h3>
<a class="indexterm" name="id2574038"></a><pre class="programlisting">const char* librdf_heuristic_get_blank_node (const char *node);</pre>
<p>
Get a blank node identifier from a node string.
</p>
<p>
Picks the blank node identifier out of a string. Looks for things
like _:ABC</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><span class="term"><em class="parameter"><code>node</code></em> :</span></td>
<td> string object to guess type
</td>
</tr>
<tr>
<td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td>
<td> the blank node identifer string or NULL if the node does not seem to be a blank node identifier
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2607059"></a><h3>
<a name="librdf-heuristic-object-is-literal"></a>librdf_heuristic_object_is_literal ()</h3>
<a class="indexterm" name="id2607072"></a><pre class="programlisting">int librdf_heuristic_object_is_literal
(const char *object);</pre>
<p>
Try to guess if an object string is a literal or a resource.
</p>
<p>
The guessing is done by assuming the object is a URL if it matches
^[<code class="function">isalnum()</code>]+:[^<code class="function">isblank()</code>]+$
</p>
<p>
This will be fooled by literals of form 'thing:non-blank-thing' but
is good enough.</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><span class="term"><em class="parameter"><code>object</code></em> :</span></td>
<td> string object to guess type
</td>
</tr>
<tr>
<td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td>
<td> non 0 if object is probably a literal
</td>
</tr>
</tbody>
</table></div>
</div>
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