libxml2-xpath.html revision c943f708f1853de4eb15e5a94cf0b35d108da87a
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47#define <a href="#XML_XPATH_CHECKNS">XML_XPATH_CHECKNS</a>; 48#define <a href="#XML_XPATH_NOVAR">XML_XPATH_NOVAR</a>; 49#define <a href="#xmlXPathNodeSetItem">xmlXPathNodeSetItem</a>(ns, index); 50#define <a href="#xmlXPathNodeSetIsEmpty">xmlXPathNodeSetIsEmpty</a>(ns); 51typedef enum <a href="#xmlXPathObjectType">xmlXPathObjectType</a>; 52typedef <a href="libxml2-xpath.html#xmlXPathVariable">xmlXPathVariable</a> * <a href="#xmlXPathVariablePtr">xmlXPathVariablePtr</a>; 53typedef struct _xmlXPathContext <a href="#xmlXPathContext">xmlXPathContext</a>; 54typedef enum <a href="#xmlXPathError">xmlXPathError</a>; 55typedef struct _xmlXPathFunct <a href="#xmlXPathFunct">xmlXPathFunct</a>; 56typedef <a href="libxml2-xpath.html#xmlXPathType">xmlXPathType</a> * <a href="#xmlXPathTypePtr">xmlXPathTypePtr</a>; 57typedef struct _xmlXPathType <a href="#xmlXPathType">xmlXPathType</a>; 58typedef <a href="libxml2-xpath.html#xmlNodeSet">xmlNodeSet</a> * <a href="#xmlNodeSetPtr">xmlNodeSetPtr</a>; 59typedef <a href="libxml2-xpath.html#xmlXPathFunct">xmlXPathFunct</a> * <a href="#xmlXPathFuncPtr">xmlXPathFuncPtr</a>; 60typedef <a href="libxml2-xpath.html#xmlXPathCompExpr">xmlXPathCompExpr</a> * <a href="#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a>; 61typedef struct _xmlXPathObject <a href="#xmlXPathObject">xmlXPathObject</a>; 62typedef struct _xmlXPathCompExpr <a href="#xmlXPathCompExpr">xmlXPathCompExpr</a>; 63typedef <a href="libxml2-xpath.html#xmlXPathContext">xmlXPathContext</a> * <a href="#xmlXPathContextPtr">xmlXPathContextPtr</a>; 64typedef <a href="libxml2-xpath.html#xmlXPathParserContext">xmlXPathParserContext</a> * <a href="#xmlXPathParserContextPtr">xmlXPathParserContextPtr</a>; 65typedef struct _xmlNodeSet <a href="#xmlNodeSet">xmlNodeSet</a>; 66typedef struct _xmlXPathVariable <a href="#xmlXPathVariable">xmlXPathVariable</a>; 67typedef <a href="libxml2-xpath.html#xmlXPathObject">xmlXPathObject</a> * <a href="#xmlXPathObjectPtr">xmlXPathObjectPtr</a>; 68typedef struct _xmlXPathAxis <a href="#xmlXPathAxis">xmlXPathAxis</a>; 69typedef <a href="libxml2-xpath.html#xmlXPathAxis">xmlXPathAxis</a> * <a href="#xmlXPathAxisPtr">xmlXPathAxisPtr</a>; 70typedef struct _xmlXPathParserContext <a href="#xmlXPathParserContext">xmlXPathParserContext</a>; 71int <a href="#xmlXPathCastNodeSetToBoolean">xmlXPathCastNodeSetToBoolean</a> (<a href="libxml2-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> ns); 72typedef <a href="libxml2-xpath.html#xmlXPathFunction">xmlXPathFunction</a> <a href="#xmlXPathFuncLookupFunc">xmlXPathFuncLookupFunc</a> (void * ctxt, <br/> const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * name, <br/> const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * ns_uri); 73<a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * <a href="#xmlXPathCastNodeToString">xmlXPathCastNodeToString</a> (<a href="libxml2-tree.html#xmlNodePtr">xmlNodePtr</a> node); 74int <a href="#xmlXPathIsNaN">xmlXPathIsNaN</a> (double val); 75int <a href="#xmlXPathContextSetCache">xmlXPathContextSetCache</a> (<a href="libxml2-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctxt, <br/> int active, <br/> int value, <br/> int options); 76<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> <a href="#xmlXPathConvertString">xmlXPathConvertString</a> (<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val); 77int <a href="#xmlXPathCompiledEvalToBoolean">xmlXPathCompiledEvalToBoolean</a> (<a href="libxml2-xpath.html#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a> comp, <br/> <a href="libxml2-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctxt); 78int <a href="#xmlXPathIsInf">xmlXPathIsInf</a> (double val); 79long <a href="#xmlXPathOrderDocElems">xmlXPathOrderDocElems</a> (<a href="libxml2-tree.html#xmlDocPtr">xmlDocPtr</a> doc); 80<a href="libxml2-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> <a href="#xmlXPathNodeSetCreate">xmlXPathNodeSetCreate</a> (<a href="libxml2-tree.html#xmlNodePtr">xmlNodePtr</a> val); 81double <a href="#xmlXPathCastBooleanToNumber">xmlXPathCastBooleanToNumber</a> (int val); 82double <a href="#xmlXPathCastNodeToNumber">xmlXPathCastNodeToNumber</a> (<a href="libxml2-tree.html#xmlNodePtr">xmlNodePtr</a> node); 83double <a href="#xmlXPathCastStringToNumber">xmlXPathCastStringToNumber</a> (const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * val); 84typedef <a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> <a href="#xmlXPathAxisFunc">xmlXPathAxisFunc</a> (<a href="libxml2-xpath.html#xmlXPathParserContextPtr">xmlXPathParserContextPtr</a> ctxt, <br/> <a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> cur); 85double <a href="#xmlXPathCastToNumber">xmlXPathCastToNumber</a> (<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val); 86int <a href="#xmlXPathCastStringToBoolean">xmlXPathCastStringToBoolean</a> (const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * val); 87<a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * <a href="#xmlXPathCastNumberToString">xmlXPathCastNumberToString</a> (double val); 88typedef <a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> <a href="#xmlXPathVariableLookupFunc">xmlXPathVariableLookupFunc</a> (void * ctxt, <br/> const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * name, <br/> const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * ns_uri); 89void <a href="#xmlXPathFreeObject">xmlXPathFreeObject</a> (<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> obj); 90int <a href="#xmlXPathEvalPredicate">xmlXPathEvalPredicate</a> (<a href="libxml2-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctxt, <br/> <a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> res); 91void <a href="#xmlXPathFreeContext">xmlXPathFreeContext</a> (<a href="libxml2-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctxt); 92<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> <a href="#xmlXPathObjectCopy">xmlXPathObjectCopy</a> (<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val); 93void <a href="#xmlXPathFreeNodeSetList">xmlXPathFreeNodeSetList</a> (<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> obj); 94<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> <a href="#xmlXPathEval">xmlXPathEval</a> (const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * str, <br/> <a href="libxml2-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctx); 95<a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * <a href="#xmlXPathCastNodeSetToString">xmlXPathCastNodeSetToString</a> (<a href="libxml2-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> ns); 96<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> <a href="#xmlXPathCompiledEval">xmlXPathCompiledEval</a> (<a href="libxml2-xpath.html#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a> comp, <br/> <a href="libxml2-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctx); 97<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> <a href="#xmlXPathEvalExpression">xmlXPathEvalExpression</a> (const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * str, <br/> <a href="libxml2-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctxt); 98void <a href="#xmlXPathInit">xmlXPathInit</a> (void); 99<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> <a href="#xmlXPathConvertBoolean">xmlXPathConvertBoolean</a> (<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val); 100typedef int <a href="#xmlXPathConvertFunc">xmlXPathConvertFunc</a> (<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> obj, <br/> int type); 101typedef void <a href="#xmlXPathFunction">xmlXPathFunction</a> (<a href="libxml2-xpath.html#xmlXPathParserContextPtr">xmlXPathParserContextPtr</a> ctxt, <br/> int nargs); 102int <a href="#xmlXPathCmpNodes">xmlXPathCmpNodes</a> (<a href="libxml2-tree.html#xmlNodePtr">xmlNodePtr</a> node1, <br/> <a href="libxml2-tree.html#xmlNodePtr">xmlNodePtr</a> node2); 103<a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * <a href="#xmlXPathCastToString">xmlXPathCastToString</a> (<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val); 104<a href="libxml2-xpath.html#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a> <a href="#xmlXPathCtxtCompile">xmlXPathCtxtCompile</a> (<a href="libxml2-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctxt, <br/> const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * str); 105typedef void <a href="#xmlXPathEvalFunc">xmlXPathEvalFunc</a> (<a href="libxml2-xpath.html#xmlXPathParserContextPtr">xmlXPathParserContextPtr</a> ctxt, <br/> int nargs); 106<a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * <a href="#xmlXPathCastBooleanToString">xmlXPathCastBooleanToString</a> (int val); 107int <a href="#xmlXPathCastNumberToBoolean">xmlXPathCastNumberToBoolean</a> (double val); 108void <a href="#xmlXPathFreeNodeSet">xmlXPathFreeNodeSet</a> (<a href="libxml2-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> obj); 109void <a href="#xmlXPathFreeCompExpr">xmlXPathFreeCompExpr</a> (<a href="libxml2-xpath.html#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a> comp); 110<a href="libxml2-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> <a href="#xmlXPathNewContext">xmlXPathNewContext</a> (<a href="libxml2-tree.html#xmlDocPtr">xmlDocPtr</a> doc); 111<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> <a href="#xmlXPathConvertNumber">xmlXPathConvertNumber</a> (<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val); 112<a href="libxml2-xpath.html#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a> <a href="#xmlXPathCompile">xmlXPathCompile</a> (const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * str); 113double <a href="#xmlXPathCastNodeSetToNumber">xmlXPathCastNodeSetToNumber</a> (<a href="libxml2-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> ns); 114int <a href="#xmlXPathCastToBoolean">xmlXPathCastToBoolean</a> (<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val); 115</pre> 116 </div> 117 <div class="refsect1" lang="en"> 118 <h2>Description</h2> 119 </div> 120 <div class="refsect1" lang="en"> 121 <h2>Details</h2> 122 <div class="refsect2" lang="en"> 123 <div class="refsect2" lang="en"><h3><a name="XML_XPATH_CHECKNS">Macro </a>XML_XPATH_CHECKNS</h3><pre class="programlisting">#define <a href="#XML_XPATH_CHECKNS">XML_XPATH_CHECKNS</a>; 124</pre><p>check namespaces at compilation</p> 125</div> 126 <hr/> 127 <div class="refsect2" lang="en"><h3><a name="XML_XPATH_NOVAR">Macro </a>XML_XPATH_NOVAR</h3><pre class="programlisting">#define <a href="#XML_XPATH_NOVAR">XML_XPATH_NOVAR</a>; 128</pre><p>forbid variables in expression</p> 129</div> 130 <hr/> 131 <div class="refsect2" lang="en"><h3><a name="xmlXPathNodeSetGetLength">Macro </a>xmlXPathNodeSetGetLength</h3><pre class="programlisting">#define <a href="#xmlXPathNodeSetGetLength">xmlXPathNodeSetGetLength</a>(ns); 132</pre><p>Implement a functionality similar to the DOM NodeList.length. Returns the number of nodes in the node-set.</p><div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>ns</tt></i>:</span></td><td>a node-set</td></tr></tbody></table></div> 133</div> 134 <hr/> 135 <div class="refsect2" lang="en"><h3><a name="xmlXPathNodeSetIsEmpty">Macro </a>xmlXPathNodeSetIsEmpty</h3><pre class="programlisting">#define <a href="#xmlXPathNodeSetIsEmpty">xmlXPathNodeSetIsEmpty</a>(ns); 136</pre><p>Checks whether @ns is empty or not. Returns %TRUE if @ns is an empty node-set.</p><div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>ns</tt></i>:</span></td><td>a node-set</td></tr></tbody></table></div> 137</div> 138 <hr/> 139 <div class="refsect2" lang="en"><h3><a name="xmlXPathNodeSetItem">Macro </a>xmlXPathNodeSetItem</h3><pre class="programlisting">#define <a href="#xmlXPathNodeSetItem">xmlXPathNodeSetItem</a>(ns, index); 140</pre><p>Implements a functionality similar to the DOM NodeList.item(). Returns the <a href="libxml2-tree.html#xmlNodePtr">xmlNodePtr</a> at the given @index in @ns or NULL if @index is out of range (0 to length-1)</p><div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>ns</tt></i>:</span></td><td>a node-set</td></tr><tr><td><span class="term"><i><tt>index</tt></i>:</span></td><td>index of a node in the set</td></tr></tbody></table></div> 141</div> 142 <hr/> 143 <div class="refsect2" lang="en"><h3><a name="xmlNodeSet">Structure </a>xmlNodeSet</h3><pre class="programlisting">struct _xmlNodeSet { 144 int nodeNr : number of nodes in the set 145 int nodeMax : size of the array as allocated 146 <a href="libxml2-tree.html#xmlNodePtr">xmlNodePtr</a> * nodeTab : array of nodes in no particular order @@ with_ns to check wether name 147} xmlNodeSet; 148</pre><p/> 149</div> 150 <hr/> 151 <div class="refsect2" lang="en"><h3><a name="xmlNodeSetPtr">Typedef </a>xmlNodeSetPtr</h3><pre class="programlisting"><a href="libxml2-xpath.html#xmlNodeSet">xmlNodeSet</a> * xmlNodeSetPtr; 152</pre><p/> 153</div> 154 <hr/> 155 <div class="refsect2" lang="en"><h3><a name="xmlXPathAxis">Structure </a>xmlXPathAxis</h3><pre class="programlisting">struct _xmlXPathAxis { 156 const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * name : the axis name 157 <a href="libxml2-xpath.html#xmlXPathAxisFunc">xmlXPathAxisFunc</a> func : the search function 158} xmlXPathAxis; 159</pre><p/> 160</div> 161 <hr/> 162 <div class="refsect2" lang="en"><h3><a name="xmlXPathAxisPtr">Typedef </a>xmlXPathAxisPtr</h3><pre class="programlisting"><a href="libxml2-xpath.html#xmlXPathAxis">xmlXPathAxis</a> * xmlXPathAxisPtr; 163</pre><p/> 164</div> 165 <hr/> 166 <div class="refsect2" lang="en"><h3><a name="xmlXPathCompExpr">Structure </a>xmlXPathCompExpr</h3><pre class="programlisting">struct _xmlXPathCompExpr { 167The content of this structure is not made public by the API. 168} xmlXPathCompExpr; 169</pre><p/> 170</div> 171 <hr/> 172 <div class="refsect2" lang="en"><h3><a name="xmlXPathCompExprPtr">Typedef </a>xmlXPathCompExprPtr</h3><pre class="programlisting"><a href="libxml2-xpath.html#xmlXPathCompExpr">xmlXPathCompExpr</a> * xmlXPathCompExprPtr; 173</pre><p/> 174</div> 175 <hr/> 176 <div class="refsect2" lang="en"><h3><a name="xmlXPathContext">Structure </a>xmlXPathContext</h3><pre class="programlisting">struct _xmlXPathContext { 177 <a href="libxml2-tree.html#xmlDocPtr">xmlDocPtr</a> doc : The current document 178 <a href="libxml2-tree.html#xmlNodePtr">xmlNodePtr</a> node : The current node 179 int nb_variables_unused : unused (hash table) 180 int max_variables_unused : unused (hash table) 181 <a href="libxml2-hash.html#xmlHashTablePtr">xmlHashTablePtr</a> varHash : Hash table of defined variables 182 int nb_types : number of defined types 183 int max_types : max number of types 184 <a href="libxml2-xpath.html#xmlXPathTypePtr">xmlXPathTypePtr</a> types : Array of defined types 185 int nb_funcs_unused : unused (hash table) 186 int max_funcs_unused : unused (hash table) 187 <a href="libxml2-hash.html#xmlHashTablePtr">xmlHashTablePtr</a> funcHash : Hash table of defined funcs 188 int nb_axis : number of defined axis 189 int max_axis : max number of axis 190 <a href="libxml2-xpath.html#xmlXPathAxisPtr">xmlXPathAxisPtr</a> axis : Array of defined axis the namespace nodes of the context node 191 <a href="libxml2-tree.html#xmlNsPtr">xmlNsPtr</a> * namespaces : Array of namespaces 192 int nsNr : number of namespace in scope 193 void * user : function to free extra variables 194 int contextSize : the context size 195 int proximityPosition : the proximity position extra stuff for XPointer 196 int xptr : is this an XPointer context? 197 <a href="libxml2-tree.html#xmlNodePtr">xmlNodePtr</a> here : for here() 198 <a href="libxml2-tree.html#xmlNodePtr">xmlNodePtr</a> origin : for origin() the set of namespace declarations in scope for the expre 199 <a href="libxml2-hash.html#xmlHashTablePtr">xmlHashTablePtr</a> nsHash : The namespaces hash table 200 <a href="libxml2-xpath.html#xmlXPathVariableLookupFunc">xmlXPathVariableLookupFunc</a> varLookupFunc : variable lookup func 201 void * varLookupData : variable lookup data Possibility to link in an extra item 202 void * extra : needed for XSLT The function name and URI when calling a function 203 const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * function 204 const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * functionURI : function lookup function and data 205 <a href="libxml2-xpath.html#xmlXPathFuncLookupFunc">xmlXPathFuncLookupFunc</a> funcLookupFunc : function lookup func 206 void * funcLookupData : function lookup data temporary namespace lists kept for walking the n 207 <a href="libxml2-tree.html#xmlNsPtr">xmlNsPtr</a> * tmpNsList : Array of namespaces 208 int tmpNsNr : number of namespaces in scope error reporting mechanism 209 void * userData : user specific data block 210 <a href="libxml2-xmlerror.html#xmlStructuredErrorFunc">xmlStructuredErrorFunc</a> error : the callback in case of errors 211 <a href="libxml2-xmlerror.html#xmlError">xmlError</a> lastError : the last error 212 <a href="libxml2-tree.html#xmlNodePtr">xmlNodePtr</a> debugNode : the source node XSLT dictionary 213 <a href="libxml2-dict.html#xmlDictPtr">xmlDictPtr</a> dict : dictionary if any 214 int flags : flags to control compilation Cache for reusal of XPath objects 215 void * cache 216} xmlXPathContext; 217</pre><p/> 218</div> 219 <hr/> 220 <div class="refsect2" lang="en"><h3><a name="xmlXPathContextPtr">Typedef </a>xmlXPathContextPtr</h3><pre class="programlisting"><a href="libxml2-xpath.html#xmlXPathContext">xmlXPathContext</a> * xmlXPathContextPtr; 221</pre><p/> 222</div> 223 <hr/> 224 <div class="refsect2" lang="en"><h3><a name="xmlXPathError">Enum </a>xmlXPathError</h3><pre class="programlisting">enum <a href="#xmlXPathError">xmlXPathError</a> { 225 <a name="XPATH_EXPRESSION_OK">XPATH_EXPRESSION_OK</a> = 0 226 <a name="XPATH_NUMBER_ERROR">XPATH_NUMBER_ERROR</a> = 1 227 <a name="XPATH_UNFINISHED_LITERAL_ERROR">XPATH_UNFINISHED_LITERAL_ERROR</a> = 2 228 <a name="XPATH_START_LITERAL_ERROR">XPATH_START_LITERAL_ERROR</a> = 3 229 <a name="XPATH_VARIABLE_REF_ERROR">XPATH_VARIABLE_REF_ERROR</a> = 4 230 <a name="XPATH_UNDEF_VARIABLE_ERROR">XPATH_UNDEF_VARIABLE_ERROR</a> = 5 231 <a name="XPATH_INVALID_PREDICATE_ERROR">XPATH_INVALID_PREDICATE_ERROR</a> = 6 232 <a name="XPATH_EXPR_ERROR">XPATH_EXPR_ERROR</a> = 7 233 <a name="XPATH_UNCLOSED_ERROR">XPATH_UNCLOSED_ERROR</a> = 8 234 <a name="XPATH_UNKNOWN_FUNC_ERROR">XPATH_UNKNOWN_FUNC_ERROR</a> = 9 235 <a name="XPATH_INVALID_OPERAND">XPATH_INVALID_OPERAND</a> = 10 236 <a name="XPATH_INVALID_TYPE">XPATH_INVALID_TYPE</a> = 11 237 <a name="XPATH_INVALID_ARITY">XPATH_INVALID_ARITY</a> = 12 238 <a name="XPATH_INVALID_CTXT_SIZE">XPATH_INVALID_CTXT_SIZE</a> = 13 239 <a name="XPATH_INVALID_CTXT_POSITION">XPATH_INVALID_CTXT_POSITION</a> = 14 240 <a name="XPATH_MEMORY_ERROR">XPATH_MEMORY_ERROR</a> = 15 241 <a name="XPTR_SYNTAX_ERROR">XPTR_SYNTAX_ERROR</a> = 16 242 <a name="XPTR_RESOURCE_ERROR">XPTR_RESOURCE_ERROR</a> = 17 243 <a name="XPTR_SUB_RESOURCE_ERROR">XPTR_SUB_RESOURCE_ERROR</a> = 18 244 <a name="XPATH_UNDEF_PREFIX_ERROR">XPATH_UNDEF_PREFIX_ERROR</a> = 19 245 <a name="XPATH_ENCODING_ERROR">XPATH_ENCODING_ERROR</a> = 20 246 <a name="XPATH_INVALID_CHAR_ERROR">XPATH_INVALID_CHAR_ERROR</a> = 21 247 <a name="XPATH_INVALID_CTXT">XPATH_INVALID_CTXT</a> = 22 248 <a name="XPATH_STACK_ERROR">XPATH_STACK_ERROR</a> = 23 249}; 250</pre><p/> 251</div> 252 <hr/> 253 <div class="refsect2" lang="en"><h3><a name="xmlXPathFuncPtr">Typedef </a>xmlXPathFuncPtr</h3><pre class="programlisting"><a href="libxml2-xpath.html#xmlXPathFunct">xmlXPathFunct</a> * xmlXPathFuncPtr; 254</pre><p/> 255</div> 256 <hr/> 257 <div class="refsect2" lang="en"><h3><a name="xmlXPathFunct">Structure </a>xmlXPathFunct</h3><pre class="programlisting">struct _xmlXPathFunct { 258 const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * name : the function name 259 <a href="libxml2-xpath.html#xmlXPathEvalFunc">xmlXPathEvalFunc</a> func : the evaluation function 260} xmlXPathFunct; 261</pre><p/> 262</div> 263 <hr/> 264 <div class="refsect2" lang="en"><h3><a name="xmlXPathObject">Structure </a>xmlXPathObject</h3><pre class="programlisting">struct _xmlXPathObject { 265 <a href="libxml2-xpath.html#xmlXPathObjectType">xmlXPathObjectType</a> type 266 <a href="libxml2-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> nodesetval 267 int boolval 268 double floatval 269 <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * stringval 270 void * user 271 int index 272 void * user2 273 int index2 274} xmlXPathObject; 275</pre><p/> 276</div> 277 <hr/> 278 <div class="refsect2" lang="en"><h3><a name="xmlXPathObjectPtr">Typedef </a>xmlXPathObjectPtr</h3><pre class="programlisting"><a href="libxml2-xpath.html#xmlXPathObject">xmlXPathObject</a> * xmlXPathObjectPtr; 279</pre><p/> 280</div> 281 <hr/> 282 <div class="refsect2" lang="en"><h3><a name="xmlXPathObjectType">Enum </a>xmlXPathObjectType</h3><pre class="programlisting">enum <a href="#xmlXPathObjectType">xmlXPathObjectType</a> { 283 <a name="XPATH_UNDEFINED">XPATH_UNDEFINED</a> = 0 284 <a name="XPATH_NODESET">XPATH_NODESET</a> = 1 285 <a name="XPATH_BOOLEAN">XPATH_BOOLEAN</a> = 2 286 <a name="XPATH_NUMBER">XPATH_NUMBER</a> = 3 287 <a name="XPATH_STRING">XPATH_STRING</a> = 4 288 <a name="XPATH_POINT">XPATH_POINT</a> = 5 289 <a name="XPATH_RANGE">XPATH_RANGE</a> = 6 290 <a name="XPATH_LOCATIONSET">XPATH_LOCATIONSET</a> = 7 291 <a name="XPATH_USERS">XPATH_USERS</a> = 8 292 <a name="XPATH_XSLT_TREE">XPATH_XSLT_TREE</a> = 9 /* An XSLT value tree, non modifiable */ 293}; 294</pre><p/> 295</div> 296 <hr/> 297 <div class="refsect2" lang="en"><h3><a name="xmlXPathParserContext">Structure </a>xmlXPathParserContext</h3><pre class="programlisting">struct _xmlXPathParserContext { 298 const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * cur : the current char being parsed 299 const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * base : the full expression 300 int error : error code 301 <a href="libxml2-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> context : the evaluation context 302 <a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> value : the current value 303 int valueNr : number of values stacked 304 int valueMax : max number of values stacked 305 <a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> * valueTab : stack of values 306 <a href="libxml2-xpath.html#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a> comp : the precompiled expression 307 int xptr : it this an XPointer expression 308 <a href="libxml2-tree.html#xmlNodePtr">xmlNodePtr</a> ancestor : used for walking preceding axis 309 int valueFrame : used to limit Pop on the stack 310} xmlXPathParserContext; 311</pre><p/> 312</div> 313 <hr/> 314 <div class="refsect2" lang="en"><h3><a name="xmlXPathParserContextPtr">Typedef </a>xmlXPathParserContextPtr</h3><pre class="programlisting"><a href="libxml2-xpath.html#xmlXPathParserContext">xmlXPathParserContext</a> * xmlXPathParserContextPtr; 315</pre><p/> 316</div> 317 <hr/> 318 <div class="refsect2" lang="en"><h3><a name="xmlXPathType">Structure </a>xmlXPathType</h3><pre class="programlisting">struct _xmlXPathType { 319 const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * name : the type name 320 <a href="libxml2-xpath.html#xmlXPathConvertFunc">xmlXPathConvertFunc</a> func : the conversion function 321} xmlXPathType; 322</pre><p/> 323</div> 324 <hr/> 325 <div class="refsect2" lang="en"><h3><a name="xmlXPathTypePtr">Typedef </a>xmlXPathTypePtr</h3><pre class="programlisting"><a href="libxml2-xpath.html#xmlXPathType">xmlXPathType</a> * xmlXPathTypePtr; 326</pre><p/> 327</div> 328 <hr/> 329 <div class="refsect2" lang="en"><h3><a name="xmlXPathVariable">Structure </a>xmlXPathVariable</h3><pre class="programlisting">struct _xmlXPathVariable { 330 const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * name : the variable name 331 <a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> value : the value 332} xmlXPathVariable; 333</pre><p/> 334</div> 335 <hr/> 336 <div class="refsect2" lang="en"><h3><a name="xmlXPathVariablePtr">Typedef </a>xmlXPathVariablePtr</h3><pre class="programlisting"><a href="libxml2-xpath.html#xmlXPathVariable">xmlXPathVariable</a> * xmlXPathVariablePtr; 337</pre><p/> 338</div> 339 <hr/> 340 <div class="refsect2" lang="en"><h3><a name="xmlXPathAxisFunc"/>Function type xmlXPathAxisFunc</h3><pre class="programlisting"><a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> xmlXPathAxisFunc (<a href="libxml2-xpath.html#xmlXPathParserContextPtr">xmlXPathParserContextPtr</a> ctxt, <br/> <a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> cur)<br/> 341</pre><p>An axis traversal function. To traverse an axis, the engine calls the first time with cur == NULL and repeat until the function returns NULL indicating the end of the axis traversal.</p> 342<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>ctxt</tt></i>:</span></td><td>the XPath interpreter context</td></tr><tr><td><span class="term"><i><tt>cur</tt></i>:</span></td><td>the previous node being explored on that axis</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the next node in that axis or NULL if at the end of the axis.</td></tr></tbody></table></div></div> 343 <hr/> 344 <div class="refsect2" lang="en"><h3><a name="xmlXPathConvertFunc"/>Function type xmlXPathConvertFunc</h3><pre class="programlisting">int xmlXPathConvertFunc (<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> obj, <br/> int type)<br/> 345</pre><p>A conversion function is associated to a type and used to cast the new type to primitive values.</p> 346<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>obj</tt></i>:</span></td><td>an XPath object</td></tr><tr><td><span class="term"><i><tt>type</tt></i>:</span></td><td>the number of the target type</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>-1 in case of error, 0 otherwise</td></tr></tbody></table></div></div> 347 <hr/> 348 <div class="refsect2" lang="en"><h3><a name="xmlXPathEvalFunc"/>Function type xmlXPathEvalFunc</h3><pre class="programlisting">void xmlXPathEvalFunc (<a href="libxml2-xpath.html#xmlXPathParserContextPtr">xmlXPathParserContextPtr</a> ctxt, <br/> int nargs)<br/> 349</pre><p>An XPath evaluation function, the parameters are on the XPath context stack.</p> 350<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>ctxt</tt></i>:</span></td><td>an XPath parser context</td></tr><tr><td><span class="term"><i><tt>nargs</tt></i>:</span></td><td>the number of arguments passed to the function</td></tr></tbody></table></div></div> 351 <hr/> 352 <div class="refsect2" lang="en"><h3><a name="xmlXPathFuncLookupFunc"/>Function type xmlXPathFuncLookupFunc</h3><pre class="programlisting"><a href="libxml2-xpath.html#xmlXPathFunction">xmlXPathFunction</a> xmlXPathFuncLookupFunc (void * ctxt, <br/> const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * name, <br/> const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * ns_uri)<br/> 353</pre><p>Prototype for callbacks used to plug function lookup in the XPath engine.</p> 354<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>ctxt</tt></i>:</span></td><td>an XPath context</td></tr><tr><td><span class="term"><i><tt>name</tt></i>:</span></td><td>name of the function</td></tr><tr><td><span class="term"><i><tt>ns_uri</tt></i>:</span></td><td>the namespace name hosting this function</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the XPath function or NULL if not found.</td></tr></tbody></table></div></div> 355 <hr/> 356 <div class="refsect2" lang="en"><h3><a name="xmlXPathFunction"/>Function type xmlXPathFunction</h3><pre class="programlisting">void xmlXPathFunction (<a href="libxml2-xpath.html#xmlXPathParserContextPtr">xmlXPathParserContextPtr</a> ctxt, <br/> int nargs)<br/> 357</pre><p>An XPath function. The arguments (if any) are popped out from the context stack and the result is pushed on the stack.</p> 358<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>ctxt</tt></i>:</span></td><td>the XPath interprestation context</td></tr><tr><td><span class="term"><i><tt>nargs</tt></i>:</span></td><td>the number of arguments</td></tr></tbody></table></div></div> 359 <hr/> 360 <div class="refsect2" lang="en"><h3><a name="xmlXPathVariableLookupFunc"/>Function type xmlXPathVariableLookupFunc</h3><pre class="programlisting"><a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> xmlXPathVariableLookupFunc (void * ctxt, <br/> const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * name, <br/> const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * ns_uri)<br/> 361</pre><p>Prototype for callbacks used to plug variable lookup in the XPath engine.</p> 362<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>ctxt</tt></i>:</span></td><td>an XPath context</td></tr><tr><td><span class="term"><i><tt>name</tt></i>:</span></td><td>name of the variable</td></tr><tr><td><span class="term"><i><tt>ns_uri</tt></i>:</span></td><td>the namespace name hosting this variable</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the XPath object value or NULL if not found.</td></tr></tbody></table></div></div> 363 <hr/> 364 <div class="refsect2" lang="en"><h3><a name="xmlXPathNAN">Variable </a>xmlXPathNAN</h3><pre class="programlisting">double xmlXPathNAN; 365</pre><p/> 366</div> 367 <hr/> 368 <div class="refsect2" lang="en"><h3><a name="xmlXPathNINF">Variable </a>xmlXPathNINF</h3><pre class="programlisting">double xmlXPathNINF; 369</pre><p/> 370</div> 371 <hr/> 372 <div class="refsect2" lang="en"><h3><a name="xmlXPathPINF">Variable </a>xmlXPathPINF</h3><pre class="programlisting">double xmlXPathPINF; 373</pre><p/> 374</div> 375 <hr/> 376 <div class="refsect2" lang="en"><h3><a name="xmlXPathCastBooleanToNumber"/>xmlXPathCastBooleanToNumber ()</h3><pre class="programlisting">double xmlXPathCastBooleanToNumber (int val)<br/> 377</pre><p>Converts a boolean to its number value</p> 378<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>a boolean</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the number value</td></tr></tbody></table></div></div> 379 <hr/> 380 <div class="refsect2" lang="en"><h3><a name="xmlXPathCastBooleanToString"/>xmlXPathCastBooleanToString ()</h3><pre class="programlisting"><a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * xmlXPathCastBooleanToString (int val)<br/> 381</pre><p>Converts a boolean to its string value.</p> 382<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>a boolean</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>a newly allocated string.</td></tr></tbody></table></div></div> 383 <hr/> 384 <div class="refsect2" lang="en"><h3><a name="xmlXPathCastNodeSetToBoolean"/>xmlXPathCastNodeSetToBoolean ()</h3><pre class="programlisting">int xmlXPathCastNodeSetToBoolean (<a href="libxml2-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> ns)<br/> 385</pre><p>Converts a node-set to its boolean value</p> 386<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>ns</tt></i>:</span></td><td>a node-set</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the boolean value</td></tr></tbody></table></div></div> 387 <hr/> 388 <div class="refsect2" lang="en"><h3><a name="xmlXPathCastNodeSetToNumber"/>xmlXPathCastNodeSetToNumber ()</h3><pre class="programlisting">double xmlXPathCastNodeSetToNumber (<a href="libxml2-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> ns)<br/> 389</pre><p>Converts a node-set to its number value</p> 390<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>ns</tt></i>:</span></td><td>a node-set</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the number value</td></tr></tbody></table></div></div> 391 <hr/> 392 <div class="refsect2" lang="en"><h3><a name="xmlXPathCastNodeSetToString"/>xmlXPathCastNodeSetToString ()</h3><pre class="programlisting"><a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * xmlXPathCastNodeSetToString (<a href="libxml2-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> ns)<br/> 393</pre><p>Converts a node-set to its string value.</p> 394<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>ns</tt></i>:</span></td><td>a node-set</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>a newly allocated string.</td></tr></tbody></table></div></div> 395 <hr/> 396 <div class="refsect2" lang="en"><h3><a name="xmlXPathCastNodeToNumber"/>xmlXPathCastNodeToNumber ()</h3><pre class="programlisting">double xmlXPathCastNodeToNumber (<a href="libxml2-tree.html#xmlNodePtr">xmlNodePtr</a> node)<br/> 397</pre><p>Converts a node to its number value</p> 398<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>node</tt></i>:</span></td><td>a node</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the number value</td></tr></tbody></table></div></div> 399 <hr/> 400 <div class="refsect2" lang="en"><h3><a name="xmlXPathCastNodeToString"/>xmlXPathCastNodeToString ()</h3><pre class="programlisting"><a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * xmlXPathCastNodeToString (<a href="libxml2-tree.html#xmlNodePtr">xmlNodePtr</a> node)<br/> 401</pre><p>Converts a node to its string value.</p> 402<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>node</tt></i>:</span></td><td>a node</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>a newly allocated string.</td></tr></tbody></table></div></div> 403 <hr/> 404 <div class="refsect2" lang="en"><h3><a name="xmlXPathCastNumberToBoolean"/>xmlXPathCastNumberToBoolean ()</h3><pre class="programlisting">int xmlXPathCastNumberToBoolean (double val)<br/> 405</pre><p>Converts a number to its boolean value</p> 406<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>a number</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the boolean value</td></tr></tbody></table></div></div> 407 <hr/> 408 <div class="refsect2" lang="en"><h3><a name="xmlXPathCastNumberToString"/>xmlXPathCastNumberToString ()</h3><pre class="programlisting"><a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * xmlXPathCastNumberToString (double val)<br/> 409</pre><p>Converts a number to its string value.</p> 410<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>a number</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>a newly allocated string.</td></tr></tbody></table></div></div> 411 <hr/> 412 <div class="refsect2" lang="en"><h3><a name="xmlXPathCastStringToBoolean"/>xmlXPathCastStringToBoolean ()</h3><pre class="programlisting">int xmlXPathCastStringToBoolean (const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * val)<br/> 413</pre><p>Converts a string to its boolean value</p> 414<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>a string</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the boolean value</td></tr></tbody></table></div></div> 415 <hr/> 416 <div class="refsect2" lang="en"><h3><a name="xmlXPathCastStringToNumber"/>xmlXPathCastStringToNumber ()</h3><pre class="programlisting">double xmlXPathCastStringToNumber (const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * val)<br/> 417</pre><p>Converts a string to its number value</p> 418<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>a string</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the number value</td></tr></tbody></table></div></div> 419 <hr/> 420 <div class="refsect2" lang="en"><h3><a name="xmlXPathCastToBoolean"/>xmlXPathCastToBoolean ()</h3><pre class="programlisting">int xmlXPathCastToBoolean (<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val)<br/> 421</pre><p>Converts an XPath object to its boolean value</p> 422<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>an XPath object</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the boolean value</td></tr></tbody></table></div></div> 423 <hr/> 424 <div class="refsect2" lang="en"><h3><a name="xmlXPathCastToNumber"/>xmlXPathCastToNumber ()</h3><pre class="programlisting">double xmlXPathCastToNumber (<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val)<br/> 425</pre><p>Converts an XPath object to its number value</p> 426<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>an XPath object</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the number value</td></tr></tbody></table></div></div> 427 <hr/> 428 <div class="refsect2" lang="en"><h3><a name="xmlXPathCastToString"/>xmlXPathCastToString ()</h3><pre class="programlisting"><a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * xmlXPathCastToString (<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val)<br/> 429</pre><p>Converts an existing object to its string() equivalent</p> 430<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>an XPath object</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the allocated string value of the object, NULL in case of error. It's up to the caller to free the string memory with xmlFree().</td></tr></tbody></table></div></div> 431 <hr/> 432 <div class="refsect2" lang="en"><h3><a name="xmlXPathCmpNodes"/>xmlXPathCmpNodes ()</h3><pre class="programlisting">int xmlXPathCmpNodes (<a href="libxml2-tree.html#xmlNodePtr">xmlNodePtr</a> node1, <br/> <a href="libxml2-tree.html#xmlNodePtr">xmlNodePtr</a> node2)<br/> 433</pre><p>Compare two nodes w.r.t document order</p> 434<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>node1</tt></i>:</span></td><td>the first node</td></tr><tr><td><span class="term"><i><tt>node2</tt></i>:</span></td><td>the second node</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>-2 in case of error 1 if first point < second point, 0 if it's the same node, -1 otherwise</td></tr></tbody></table></div></div> 435 <hr/> 436 <div class="refsect2" lang="en"><h3><a name="xmlXPathCompile"/>xmlXPathCompile ()</h3><pre class="programlisting"><a href="libxml2-xpath.html#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a> xmlXPathCompile (const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * str)<br/> 437</pre><p>Compile an XPath expression</p> 438<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>str</tt></i>:</span></td><td>the XPath expression</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the <a href="libxml2-xpath.html#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a> resulting from the compilation or NULL. the caller has to free the object.</td></tr></tbody></table></div></div> 439 <hr/> 440 <div class="refsect2" lang="en"><h3><a name="xmlXPathCompiledEval"/>xmlXPathCompiledEval ()</h3><pre class="programlisting"><a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> xmlXPathCompiledEval (<a href="libxml2-xpath.html#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a> comp, <br/> <a href="libxml2-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctx)<br/> 441</pre><p>Evaluate the Precompiled XPath expression in the given context.</p> 442<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>comp</tt></i>:</span></td><td>the compiled XPath expression</td></tr><tr><td><span class="term"><i><tt>ctx</tt></i>:</span></td><td>the XPath context</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the <a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> resulting from the evaluation or NULL. the caller has to free the object.</td></tr></tbody></table></div></div> 443 <hr/> 444 <div class="refsect2" lang="en"><h3><a name="xmlXPathCompiledEvalToBoolean"/>xmlXPathCompiledEvalToBoolean ()</h3><pre class="programlisting">int xmlXPathCompiledEvalToBoolean (<a href="libxml2-xpath.html#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a> comp, <br/> <a href="libxml2-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctxt)<br/> 445</pre><p>Applies the XPath boolean() function on the result of the given compiled expression.</p> 446<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>comp</tt></i>:</span></td><td>the compiled XPath expression</td></tr><tr><td><span class="term"><i><tt>ctxt</tt></i>:</span></td><td>the XPath context</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>1 if the expression evaluated to true, 0 if to false and -1 in API and internal errors.</td></tr></tbody></table></div></div> 447 <hr/> 448 <div class="refsect2" lang="en"><h3><a name="xmlXPathContextSetCache"/>xmlXPathContextSetCache ()</h3><pre class="programlisting">int xmlXPathContextSetCache (<a href="libxml2-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctxt, <br/> int active, <br/> int value, <br/> int options)<br/> 449</pre><p>Creates/frees an object cache on the XPath context. If activates XPath objects (xmlXPathObject) will be cached internally to be reused. @options: 0: This will set the XPath object caching: @value: This will set the maximum number of XPath objects to be cached per slot There are 5 slots for: node-set, string, number, boolean, and misc objects. Use <0 for the default number (100). Other values for @options have currently no effect.</p> 450<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>ctxt</tt></i>:</span></td><td>the XPath context</td></tr><tr><td><span class="term"><i><tt>active</tt></i>:</span></td><td>enables/disables (creates/frees) the cache</td></tr><tr><td><span class="term"><i><tt>value</tt></i>:</span></td><td>a value with semantics dependant on @options</td></tr><tr><td><span class="term"><i><tt>options</tt></i>:</span></td><td>options (currently only the value 0 is used)</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>0 if the setting succeeded, and -1 on API or internal errors.</td></tr></tbody></table></div></div> 451 <hr/> 452 <div class="refsect2" lang="en"><h3><a name="xmlXPathConvertBoolean"/>xmlXPathConvertBoolean ()</h3><pre class="programlisting"><a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> xmlXPathConvertBoolean (<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val)<br/> 453</pre><p>Converts an existing object to its boolean() equivalent</p> 454<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>an XPath object</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the new object, the old one is freed (or the operation is done directly on @val)</td></tr></tbody></table></div></div> 455 <hr/> 456 <div class="refsect2" lang="en"><h3><a name="xmlXPathConvertNumber"/>xmlXPathConvertNumber ()</h3><pre class="programlisting"><a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> xmlXPathConvertNumber (<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val)<br/> 457</pre><p>Converts an existing object to its number() equivalent</p> 458<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>an XPath object</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the new object, the old one is freed (or the operation is done directly on @val)</td></tr></tbody></table></div></div> 459 <hr/> 460 <div class="refsect2" lang="en"><h3><a name="xmlXPathConvertString"/>xmlXPathConvertString ()</h3><pre class="programlisting"><a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> xmlXPathConvertString (<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val)<br/> 461</pre><p>Converts an existing object to its string() equivalent</p> 462<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>an XPath object</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the new object, the old one is freed (or the operation is done directly on @val)</td></tr></tbody></table></div></div> 463 <hr/> 464 <div class="refsect2" lang="en"><h3><a name="xmlXPathCtxtCompile"/>xmlXPathCtxtCompile ()</h3><pre class="programlisting"><a href="libxml2-xpath.html#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a> xmlXPathCtxtCompile (<a href="libxml2-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctxt, <br/> const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * str)<br/> 465</pre><p>Compile an XPath expression</p> 466<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>ctxt</tt></i>:</span></td><td>an XPath context</td></tr><tr><td><span class="term"><i><tt>str</tt></i>:</span></td><td>the XPath expression</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the <a href="libxml2-xpath.html#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a> resulting from the compilation or NULL. the caller has to free the object.</td></tr></tbody></table></div></div> 467 <hr/> 468 <div class="refsect2" lang="en"><h3><a name="xmlXPathEval"/>xmlXPathEval ()</h3><pre class="programlisting"><a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> xmlXPathEval (const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * str, <br/> <a href="libxml2-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctx)<br/> 469</pre><p>Evaluate the XPath Location Path in the given context.</p> 470<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>str</tt></i>:</span></td><td>the XPath expression</td></tr><tr><td><span class="term"><i><tt>ctx</tt></i>:</span></td><td>the XPath context</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the <a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> resulting from the evaluation or NULL. the caller has to free the object.</td></tr></tbody></table></div></div> 471 <hr/> 472 <div class="refsect2" lang="en"><h3><a name="xmlXPathEvalExpression"/>xmlXPathEvalExpression ()</h3><pre class="programlisting"><a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> xmlXPathEvalExpression (const <a href="libxml2-xmlstring.html#xmlChar">xmlChar</a> * str, <br/> <a href="libxml2-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctxt)<br/> 473</pre><p>Evaluate the XPath expression in the given context.</p> 474<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>str</tt></i>:</span></td><td>the XPath expression</td></tr><tr><td><span class="term"><i><tt>ctxt</tt></i>:</span></td><td>the XPath context</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the <a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> resulting from the evaluation or NULL. the caller has to free the object.</td></tr></tbody></table></div></div> 475 <hr/> 476 <div class="refsect2" lang="en"><h3><a name="xmlXPathEvalPredicate"/>xmlXPathEvalPredicate ()</h3><pre class="programlisting">int xmlXPathEvalPredicate (<a href="libxml2-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctxt, <br/> <a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> res)<br/> 477</pre><p>Evaluate a predicate result for the current node. A PredicateExpr is evaluated by evaluating the Expr and converting the result to a boolean. If the result is a number, the result will be converted to true if the number is equal to the position of the context node in the context node list (as returned by the position function) and will be converted to false otherwise; if the result is not a number, then the result will be converted as if by a call to the boolean function.</p> 478<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>ctxt</tt></i>:</span></td><td>the XPath context</td></tr><tr><td><span class="term"><i><tt>res</tt></i>:</span></td><td>the Predicate Expression evaluation result</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>1 if predicate is true, 0 otherwise</td></tr></tbody></table></div></div> 479 <hr/> 480 <div class="refsect2" lang="en"><h3><a name="xmlXPathFreeCompExpr"/>xmlXPathFreeCompExpr ()</h3><pre class="programlisting">void xmlXPathFreeCompExpr (<a href="libxml2-xpath.html#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a> comp)<br/> 481</pre><p>Free up the memory allocated by @comp</p> 482<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>comp</tt></i>:</span></td><td>an XPATH comp</td></tr></tbody></table></div></div> 483 <hr/> 484 <div class="refsect2" lang="en"><h3><a name="xmlXPathFreeContext"/>xmlXPathFreeContext ()</h3><pre class="programlisting">void xmlXPathFreeContext (<a href="libxml2-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctxt)<br/> 485</pre><p>Free up an <a href="libxml2-xpath.html#xmlXPathContext">xmlXPathContext</a></p> 486<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>ctxt</tt></i>:</span></td><td>the context to free</td></tr></tbody></table></div></div> 487 <hr/> 488 <div class="refsect2" lang="en"><h3><a name="xmlXPathFreeNodeSet"/>xmlXPathFreeNodeSet ()</h3><pre class="programlisting">void xmlXPathFreeNodeSet (<a href="libxml2-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> obj)<br/> 489</pre><p>Free the NodeSet compound (not the actual nodes !).</p> 490<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>obj</tt></i>:</span></td><td>the <a href="libxml2-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> to free</td></tr></tbody></table></div></div> 491 <hr/> 492 <div class="refsect2" lang="en"><h3><a name="xmlXPathFreeNodeSetList"/>xmlXPathFreeNodeSetList ()</h3><pre class="programlisting">void xmlXPathFreeNodeSetList (<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> obj)<br/> 493</pre><p>Free up the <a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> @obj but don't deallocate the objects in the list contrary to xmlXPathFreeObject().</p> 494<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>obj</tt></i>:</span></td><td>an existing NodeSetList object</td></tr></tbody></table></div></div> 495 <hr/> 496 <div class="refsect2" lang="en"><h3><a name="xmlXPathFreeObject"/>xmlXPathFreeObject ()</h3><pre class="programlisting">void xmlXPathFreeObject (<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> obj)<br/> 497</pre><p>Free up an <a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> object.</p> 498<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>obj</tt></i>:</span></td><td>the object to free</td></tr></tbody></table></div></div> 499 <hr/> 500 <div class="refsect2" lang="en"><h3><a name="xmlXPathInit"/>xmlXPathInit ()</h3><pre class="programlisting">void xmlXPathInit (void)<br/> 501</pre><p>Initialize the XPath environment</p> 502</div> 503 <hr/> 504 <div class="refsect2" lang="en"><h3><a name="xmlXPathIsInf"/>xmlXPathIsInf ()</h3><pre class="programlisting">int xmlXPathIsInf (double val)<br/> 505</pre><p>Provides a portable isinf() function to detect whether a double is a +Infinite or -Infinite. Based on trio code http://sourceforge.net/projects/ctrio/</p> 506<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>a double value</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>1 vi the value is +Infinite, -1 if -Infinite, 0 otherwise</td></tr></tbody></table></div></div> 507 <hr/> 508 <div class="refsect2" lang="en"><h3><a name="xmlXPathIsNaN"/>xmlXPathIsNaN ()</h3><pre class="programlisting">int xmlXPathIsNaN (double val)<br/> 509</pre><p>Provides a portable isnan() function to detect whether a double is a NotaNumber. Based on trio code http://sourceforge.net/projects/ctrio/</p> 510<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>a double value</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>1 if the value is a NaN, 0 otherwise</td></tr></tbody></table></div></div> 511 <hr/> 512 <div class="refsect2" lang="en"><h3><a name="xmlXPathNewContext"/>xmlXPathNewContext ()</h3><pre class="programlisting"><a href="libxml2-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> xmlXPathNewContext (<a href="libxml2-tree.html#xmlDocPtr">xmlDocPtr</a> doc)<br/> 513</pre><p>Create a new <a href="libxml2-xpath.html#xmlXPathContext">xmlXPathContext</a></p> 514<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>doc</tt></i>:</span></td><td>the XML document</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the <a href="libxml2-xpath.html#xmlXPathContext">xmlXPathContext</a> just allocated. The caller will need to free it.</td></tr></tbody></table></div></div> 515 <hr/> 516 <div class="refsect2" lang="en"><h3><a name="xmlXPathNodeSetCreate"/>xmlXPathNodeSetCreate ()</h3><pre class="programlisting"><a href="libxml2-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> xmlXPathNodeSetCreate (<a href="libxml2-tree.html#xmlNodePtr">xmlNodePtr</a> val)<br/> 517</pre><p>Create a new <a href="libxml2-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> of type double and of value @val</p> 518<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>an initial xmlNodePtr, or NULL</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the newly created object.</td></tr></tbody></table></div></div> 519 <hr/> 520 <div class="refsect2" lang="en"><h3><a name="xmlXPathObjectCopy"/>xmlXPathObjectCopy ()</h3><pre class="programlisting"><a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> xmlXPathObjectCopy (<a href="libxml2-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val)<br/> 521</pre><p>allocate a new copy of a given object</p> 522<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>val</tt></i>:</span></td><td>the original object</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the newly created object.</td></tr></tbody></table></div></div> 523 <hr/> 524 <div class="refsect2" lang="en"><h3><a name="xmlXPathOrderDocElems"/>xmlXPathOrderDocElems ()</h3><pre class="programlisting">long xmlXPathOrderDocElems (<a href="libxml2-tree.html#xmlDocPtr">xmlDocPtr</a> doc)<br/> 525</pre><p>Call this routine to speed up XPath computation on static documents. This stamps all the element nodes with the document order Like for line information, the order is kept in the element->content field, the value stored is actually - the node number (starting at -1) to be able to differentiate from line numbers.</p> 526<div class="variablelist"><table border="0"><col align="left"/><tbody><tr><td><span class="term"><i><tt>doc</tt></i>:</span></td><td>an input document</td></tr><tr><td><span class="term"><i><tt>Returns</tt></i>:</span></td><td>the number of elements found in the document or -1 in case of error.</td></tr></tbody></table></div></div> 527 <hr/> 528 </div> 529 </div> 530 </body> 531</html> 532
