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<a href="#id2622134" class="shortcut">Description</a></nobr></td></tr>
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<div class="refentry" lang="en">
<a name="rasqal-section-variable"></a><div class="titlepage"></div>
<div class="refnamediv"><table width="100%"><tr>
<td valign="top">
<h2>
<a name="id2591761"></a><span class="refentrytitle">Variables</span>
</h2>
<p>Variables — Variable with names and literal value.</p>
</td>
<td valign="top" align="right"></td>
</tr></table></div>
<div class="refsynopsisdiv">
<h2>Synopsis</h2>
<pre class="synopsis">
<a href="rasqal-section-variable.html#rasqal-variable">rasqal_variable</a>;
<a href="rasqal-section-variable.html#rasqal-variable">rasqal_variable</a>* <a href="rasqal-section-variable.html#rasqal-new-variable">rasqal_new_variable</a> (<a href="rasqal-section-query.html#rasqal-query">rasqal_query</a> *rq,
unsigned char *name,
<a href="rasqal-section-literal.html#rasqal-literal">rasqal_literal</a> *value);
<a href="rasqal-section-variable.html#rasqal-variable">rasqal_variable</a>* <a href="rasqal-section-variable.html#rasqal-new-variable-typed">rasqal_new_variable_typed</a> (<a href="rasqal-section-query.html#rasqal-query">rasqal_query</a> *rq,
<a href="rasqal-section-variable.html#rasqal-variable-type">rasqal_variable_type</a> type,
unsigned char *name,
<a href="rasqal-section-literal.html#rasqal-literal">rasqal_literal</a> *value);
void <a href="rasqal-section-variable.html#rasqal-free-variable">rasqal_free_variable</a> (<a href="rasqal-section-variable.html#rasqal-variable">rasqal_variable</a> *v);
void <a href="rasqal-section-variable.html#rasqal-variable-print">rasqal_variable_print</a> (<a href="rasqal-section-variable.html#rasqal-variable">rasqal_variable</a> *v,
FILE *fh);
void <a href="rasqal-section-variable.html#rasqal-variable-set-value">rasqal_variable_set_value</a> (<a href="rasqal-section-variable.html#rasqal-variable">rasqal_variable</a> *v,
<a href="rasqal-section-literal.html#rasqal-literal">rasqal_literal</a> *l);
enum <a href="rasqal-section-variable.html#rasqal-variable-type">rasqal_variable_type</a>;
</pre>
</div>
<div class="refsect1" lang="en">
<a name="id2622134"></a><h2>Description</h2>
<p>
A class to hold a variable with optional name and a
<a href="rasqal-section-literal.html#rasqal-literal"><span class="type">rasqal_literal</span></a> value. The name is not required for SPARQL
anonymous variables, when constructed with
<a href="rasqal-section-variable.html#rasqal-new-variable-typed"><code class="function">rasqal_new_variable_typed()</code></a> and type <a href="rasqal-section-variable.html#RASQAL-VARIABLE-TYPE-ANONYMOUS:CAPS"><span class="type">RASQAL_VARIABLE_TYPE_ANONYMOUS</span></a>.
</p>
</div>
<div class="refsect1" lang="en">
<a name="id2622174"></a><h2>Details</h2>
<div class="refsect2" lang="en">
<a name="id2620726"></a><h3>
<a name="rasqal-variable"></a>rasqal_variable</h3>
<a class="indexterm" name="id2620738"></a><pre class="programlisting">typedef struct {
const unsigned char *name;
rasqal_literal* value;
int offset;
rasqal_variable_type type;
} rasqal_variable;
</pre>
<p>
Binding between a variable name and a value.
</p>
<p>
Includes internal field <em class="parameter"><code>offset</code></em> for recording the offset into the
(internal) rasqal_query variables array.</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><span class="term">const unsigned char *<em class="structfield"><code>name</code></em>;</span></td>
<td> Variable name.
</td>
</tr>
<tr>
<td><span class="term"><a href="rasqal-section-literal.html#rasqal-literal">rasqal_literal</a> *<em class="structfield"><code>value</code></em>;</span></td>
<td> Variable value or NULL if unbound.
</td>
</tr>
<tr>
<td><span class="term">int <em class="structfield"><code>offset</code></em>;</span></td>
<td> Internal.
</td>
</tr>
<tr>
<td><span class="term"><a href="rasqal-section-variable.html#rasqal-variable-type">rasqal_variable_type</a> <em class="structfield"><code>type</code></em>;</span></td>
<td> Variable type.
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2620859"></a><h3>
<a name="rasqal-new-variable"></a>rasqal_new_variable ()</h3>
<a class="indexterm" name="id2620872"></a><pre class="programlisting"><a href="rasqal-section-variable.html#rasqal-variable">rasqal_variable</a>* rasqal_new_variable (<a href="rasqal-section-query.html#rasqal-query">rasqal_query</a> *rq,
unsigned char *name,
<a href="rasqal-section-literal.html#rasqal-literal">rasqal_literal</a> *value);</pre>
<p>
Constructor - Create a new Rasqal normal variable.
</p>
<p>
The variable must be associated with a query, since variable
names are only significant with a single query.
</p>
<p>
This creates a regular variable that can be returned of type
RASQAL_VARIABLE_TYPE_NORMAL. Use rasqal_new_variable_typed
to create other variables.
</p>
<p>
The <em class="parameter"><code>name</code></em> and <em class="parameter"><code>value</code></em> become owned by the rasqal_variable structure</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><span class="term"><em class="parameter"><code>rq</code></em> :</span></td>
<td> <a href="rasqal-section-query.html#rasqal-query"><span class="type">rasqal_query</span></a> to associate the variable with
</td>
</tr>
<tr>
<td><span class="term"><em class="parameter"><code>name</code></em> :</span></td>
<td> variable name
</td>
</tr>
<tr>
<td><span class="term"><em class="parameter"><code>value</code></em> :</span></td>
<td> variable <a href="rasqal-section-literal.html#rasqal-literal"><span class="type">rasqal_literal</span></a> value (or NULL)
</td>
</tr>
<tr>
<td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td>
<td> a new <a href="rasqal-section-variable.html#rasqal-variable"><span class="type">rasqal_variable</span></a> or NULL on failure.
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2618544"></a><h3>
<a name="rasqal-new-variable-typed"></a>rasqal_new_variable_typed ()</h3>
<a class="indexterm" name="id2618555"></a><pre class="programlisting"><a href="rasqal-section-variable.html#rasqal-variable">rasqal_variable</a>* rasqal_new_variable_typed (<a href="rasqal-section-query.html#rasqal-query">rasqal_query</a> *rq,
<a href="rasqal-section-variable.html#rasqal-variable-type">rasqal_variable_type</a> type,
unsigned char *name,
<a href="rasqal-section-literal.html#rasqal-literal">rasqal_literal</a> *value);</pre>
<p>
Constructor - Create a new typed Rasqal variable.
</p>
<p>
The variable must be associated with a query, since variable
names are only significant with a single query.
</p>
<p>
The <em class="parameter"><code>name</code></em> and <em class="parameter"><code>value</code></em> become owned by the rasqal_variable structure</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><span class="term"><em class="parameter"><code>rq</code></em> :</span></td>
<td> <a href="rasqal-section-query.html#rasqal-query"><span class="type">rasqal_query</span></a> to associate the variable with
</td>
</tr>
<tr>
<td><span class="term"><em class="parameter"><code>type</code></em> :</span></td>
<td> variable type defined by enumeration rasqal_variable_type
</td>
</tr>
<tr>
<td><span class="term"><em class="parameter"><code>name</code></em> :</span></td>
<td> variable name
</td>
</tr>
<tr>
<td><span class="term"><em class="parameter"><code>value</code></em> :</span></td>
<td> variable <a href="rasqal-section-literal.html#rasqal-literal"><span class="type">rasqal_literal</span></a> value (or NULL)
</td>
</tr>
<tr>
<td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td>
<td> a new <a href="rasqal-section-variable.html#rasqal-variable"><span class="type">rasqal_variable</span></a> or NULL on failure.
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2618722"></a><h3>
<a name="rasqal-free-variable"></a>rasqal_free_variable ()</h3>
<a class="indexterm" name="id2618734"></a><pre class="programlisting">void rasqal_free_variable (<a href="rasqal-section-variable.html#rasqal-variable">rasqal_variable</a> *v);</pre>
<p>
Destructor - Destroy a Rasqal variable object.</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody><tr>
<td><span class="term"><em class="parameter"><code>v</code></em> :</span></td>
<td> <a href="rasqal-section-variable.html#rasqal-variable"><span class="type">rasqal_variable</span></a> object
</td>
</tr></tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2618791"></a><h3>
<a name="rasqal-variable-print"></a>rasqal_variable_print ()</h3>
<a class="indexterm" name="id2618802"></a><pre class="programlisting">void rasqal_variable_print (<a href="rasqal-section-variable.html#rasqal-variable">rasqal_variable</a> *v,
FILE *fh);</pre>
<p>
Print a Rasqal variable in a debug format.
</p>
<p>
The print debug format may change in any release.</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><span class="term"><em class="parameter"><code>v</code></em> :</span></td>
<td> the <a href="rasqal-section-variable.html#rasqal-variable"><span class="type">rasqal_variable</span></a> object
</td>
</tr>
<tr>
<td><span class="term"><em class="parameter"><code>fh</code></em> :</span></td>
<td> the <span class="type">FILE</span>* handle to print to
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2618892"></a><h3>
<a name="rasqal-variable-set-value"></a>rasqal_variable_set_value ()</h3>
<a class="indexterm" name="id2618903"></a><pre class="programlisting">void rasqal_variable_set_value (<a href="rasqal-section-variable.html#rasqal-variable">rasqal_variable</a> *v,
<a href="rasqal-section-literal.html#rasqal-literal">rasqal_literal</a> *l);</pre>
<p>
Set the value of a Rasqal variable.
</p>
<p>
The variable value is an input parameter and is copied in, not shared.
If the variable value is NULL, any existing value is deleted.</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><span class="term"><em class="parameter"><code>v</code></em> :</span></td>
<td> the <a href="rasqal-section-variable.html#rasqal-variable"><span class="type">rasqal_variable</span></a> object
</td>
</tr>
<tr>
<td><span class="term"><em class="parameter"><code>l</code></em> :</span></td>
<td> the <a href="rasqal-section-literal.html#rasqal-literal"><span class="type">rasqal_literal</span></a> value to set (or NULL)
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2618995"></a><h3>
<a name="rasqal-variable-type"></a>enum rasqal_variable_type</h3>
<a class="indexterm" name="id2619006"></a><pre class="programlisting">typedef enum {
RASQAL_VARIABLE_TYPE_UNKNOWN = 0,
RASQAL_VARIABLE_TYPE_NORMAL = 1,
RASQAL_VARIABLE_TYPE_ANONYMOUS = 2
} rasqal_variable_type;
</pre>
<p>
Rasqal variable types.
</p>
<p>
ANONYMOUS can be used in queries but cannot be returned in a
result.</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><span class="term"><a name="RASQAL-VARIABLE-TYPE-UNKNOWN:CAPS"></a><code class="literal">RASQAL_VARIABLE_TYPE_UNKNOWN</code></span></td>
<td> Internal.
</td>
</tr>
<tr>
<td><span class="term"><a name="RASQAL-VARIABLE-TYPE-NORMAL:CAPS"></a><code class="literal">RASQAL_VARIABLE_TYPE_NORMAL</code></span></td>
<td> The regular variable type.
</td>
</tr>
<tr>
<td><span class="term"><a name="RASQAL-VARIABLE-TYPE-ANONYMOUS:CAPS"></a><code class="literal">RASQAL_VARIABLE_TYPE_ANONYMOUS</code></span></td>
<td> Anonymous variable type.
</td>
</tr>
</tbody>
</table></div>
</div>
</div>
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