libxml2/doc/html/libxml-xpath.html

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  31       </style><link rel="home" href="index.html" title="Gnome XML Library Reference Manual"><link rel="up" href="libxml-lib.html" title="Libxml Library Reference"><link rel="previous" href="libxml-HTMLtree.html" title="HTMLtree"><link rel="next" href="libxml-xpathInternals.html" title="xpathInternals"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><table xmlns="http://www.w3.org/TR/xhtml1/transitional" class="navigation" width="100%" summary="Navigation header" cellpadding="2" cellspacing="2"><tr valign="middle"><td><a accesskey="p" href="libxml-HTMLtree.html"><img src="left.png" width="24" height="24" border="0" alt="Prev"></img></a></td><td><a accesskey="u" href="libxml-lib.html"><img src="up.png" width="24" height="24" border="0" alt="Up"></img></a></td><td><a accesskey="h" href="index.html"><img src="home.png" width="24" height="24" border="0" alt="Home"></img></a></td><th width="100%" align="center">Gnome XML Library Reference Manual</th><td><a accesskey="n" href="libxml-xpathInternals.html"><img src="right.png" width="24" height="24" border="0" alt="Next"></img></a></td></tr></table><div class="refentry" lang="en"><a name="libxml-xpath"></a><div class="titlepage"></div><div class="refnamediv"><h2>xpath</h2><p>xpath &#8212; </p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><pre class="synopsis">
  32
  33
  34
  35 struct      <a href="libxml-xpath.html#xmlXPathContext">xmlXPathContext</a>;
  36 typedef     <a href="libxml-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a>;
  37 struct      <a href="libxml-xpath.html#xmlXPathParserContext">xmlXPathParserContext</a>;
  38 typedef     <a href="libxml-xpath.html#xmlXPathParserContextPtr">xmlXPathParserContextPtr</a>;
  39 enum        <a href="libxml-xpath.html#xmlXPathError">xmlXPathError</a>;
  40 struct      <a href="libxml-xpath.html#xmlNodeSet">xmlNodeSet</a>;
  41 typedef     <a href="libxml-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a>;
  42 enum        <a href="libxml-xpath.html#xmlXPathObjectType">xmlXPathObjectType</a>;
  43 struct      <a href="libxml-xpath.html#xmlXPathObject">xmlXPathObject</a>;
  44 typedef     <a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a>;
  45 int         (<a href="libxml-xpath.html#xmlXPathConvertFunc">*xmlXPathConvertFunc</a>)          (<a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> obj,
  46                                              int type);
  47 struct      <a href="libxml-xpath.html#xmlXPathType">xmlXPathType</a>;
  48 typedef     <a href="libxml-xpath.html#xmlXPathTypePtr">xmlXPathTypePtr</a>;
  49 struct      <a href="libxml-xpath.html#xmlXPathVariable">xmlXPathVariable</a>;
  50 typedef     <a href="libxml-xpath.html#xmlXPathVariablePtr">xmlXPathVariablePtr</a>;
  51 void        (<a href="libxml-xpath.html#xmlXPathEvalFunc">*xmlXPathEvalFunc</a>)             (<a href="libxml-xpath.html#xmlXPathParserContextPtr">xmlXPathParserContextPtr</a> ctxt,
  52                                              int nargs);
  53 struct      <a href="libxml-xpath.html#xmlXPathFunct">xmlXPathFunct</a>;
  54 typedef     <a href="libxml-xpath.html#xmlXPathFuncPtr">xmlXPathFuncPtr</a>;
  55 <a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> (<a href="libxml-xpath.html#xmlXPathAxisFunc">*xmlXPathAxisFunc</a>)       (<a href="libxml-xpath.html#xmlXPathParserContextPtr">xmlXPathParserContextPtr</a> ctxt,
  56                                              <a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> cur);
  57 struct      <a href="libxml-xpath.html#xmlXPathAxis">xmlXPathAxis</a>;
  58 typedef     <a href="libxml-xpath.html#xmlXPathAxisPtr">xmlXPathAxisPtr</a>;
  59 struct      <a href="libxml-xpath.html#xmlXPathCompExpr">xmlXPathCompExpr</a>;
  60 typedef     <a href="libxml-xpath.html#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a>;
  61 void        (<a href="libxml-xpath.html#xmlXPathFunction">*xmlXPathFunction</a>)             (<a href="libxml-xpath.html#xmlXPathParserContextPtr">xmlXPathParserContextPtr</a> ctxt,
  62                                              int nargs);
  63 int         <a href="libxml-xpath.html#xmlXPathIsNaN">xmlXPathIsNaN</a>                   (<GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="double">double</GTKDOCLINK> val);
  64 int         <a href="libxml-xpath.html#xmlXPathIsInf">xmlXPathIsInf</a>                   (<GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="double">double</GTKDOCLINK> val);
  65 #define     <a href="libxml-xpath.html#xmlXPathNodeSetGetLength">xmlXPathNodeSetGetLength</a>        (ns)
  66 #define     <a href="libxml-xpath.html#xmlXPathNodeSetItem">xmlXPathNodeSetItem</a>             (ns, index)
  67 #define     <a href="libxml-xpath.html#xmlXPathNodeSetIsEmpty">xmlXPathNodeSetIsEmpty</a>          (ns)
  68 void        <a href="libxml-xpath.html#xmlXPathFreeObject">xmlXPathFreeObject</a>              (<a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> obj);
  69 <a href="libxml-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> <a href="libxml-xpath.html#xmlXPathNodeSetCreate">xmlXPathNodeSetCreate</a>         (<a href="libxml-tree.html#xmlNodePtr">xmlNodePtr</a> val);
  70 void        <a href="libxml-xpath.html#xmlXPathFreeNodeSetList">xmlXPathFreeNodeSetList</a>         (<a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> obj);
  71 void        <a href="libxml-xpath.html#xmlXPathFreeNodeSet">xmlXPathFreeNodeSet</a>             (<a href="libxml-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> obj);
  72 <a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> <a href="libxml-xpath.html#xmlXPathObjectCopy">xmlXPathObjectCopy</a>        (<a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val);
  73 int         <a href="libxml-xpath.html#xmlXPathCmpNodes">xmlXPathCmpNodes</a>                (<a href="libxml-tree.html#xmlNodePtr">xmlNodePtr</a> node1,
  74                                              <a href="libxml-tree.html#xmlNodePtr">xmlNodePtr</a> node2);
  75 int         <a href="libxml-xpath.html#xmlXPathCastNumberToBoolean">xmlXPathCastNumberToBoolean</a>     (<GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="double">double</GTKDOCLINK> val);
  76 int         <a href="libxml-xpath.html#xmlXPathCastStringToBoolean">xmlXPathCastStringToBoolean</a>     (const <a href="libxml-tree.html#xmlChar">xmlChar</a> *val);
  77 int         <a href="libxml-xpath.html#xmlXPathCastNodeSetToBoolean">xmlXPathCastNodeSetToBoolean</a>    (<a href="libxml-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> ns);
  78 int         <a href="libxml-xpath.html#xmlXPathCastToBoolean">xmlXPathCastToBoolean</a>           (<a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val);
  79 <GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="double">double</GTKDOCLINK>      <a href="libxml-xpath.html#xmlXPathCastBooleanToNumber">xmlXPathCastBooleanToNumber</a>     (int val);
  80 <GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="double">double</GTKDOCLINK>      <a href="libxml-xpath.html#xmlXPathCastStringToNumber">xmlXPathCastStringToNumber</a>      (const <a href="libxml-tree.html#xmlChar">xmlChar</a> *val);
  81 <GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="double">double</GTKDOCLINK>      <a href="libxml-xpath.html#xmlXPathCastNodeToNumber">xmlXPathCastNodeToNumber</a>        (<a href="libxml-tree.html#xmlNodePtr">xmlNodePtr</a> node);
  82 <GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="double">double</GTKDOCLINK>      <a href="libxml-xpath.html#xmlXPathCastNodeSetToNumber">xmlXPathCastNodeSetToNumber</a>     (<a href="libxml-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> ns);
  83 <GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="double">double</GTKDOCLINK>      <a href="libxml-xpath.html#xmlXPathCastToNumber">xmlXPathCastToNumber</a>            (<a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val);
  84 <a href="libxml-tree.html#xmlChar">xmlChar</a>*    <a href="libxml-xpath.html#xmlXPathCastBooleanToString">xmlXPathCastBooleanToString</a>     (int val);
  85 <a href="libxml-tree.html#xmlChar">xmlChar</a>*    <a href="libxml-xpath.html#xmlXPathCastNumberToString">xmlXPathCastNumberToString</a>      (<GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="double">double</GTKDOCLINK> val);
  86 <a href="libxml-tree.html#xmlChar">xmlChar</a>*    <a href="libxml-xpath.html#xmlXPathCastNodeToString">xmlXPathCastNodeToString</a>        (<a href="libxml-tree.html#xmlNodePtr">xmlNodePtr</a> node);
  87 <a href="libxml-tree.html#xmlChar">xmlChar</a>*    <a href="libxml-xpath.html#xmlXPathCastNodeSetToString">xmlXPathCastNodeSetToString</a>     (<a href="libxml-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> ns);
  88 <a href="libxml-tree.html#xmlChar">xmlChar</a>*    <a href="libxml-xpath.html#xmlXPathCastToString">xmlXPathCastToString</a>            (<a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val);
  89 <a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> <a href="libxml-xpath.html#xmlXPathConvertBoolean">xmlXPathConvertBoolean</a>    (<a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val);
  90 <a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> <a href="libxml-xpath.html#xmlXPathConvertNumber">xmlXPathConvertNumber</a>     (<a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val);
  91 <a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> <a href="libxml-xpath.html#xmlXPathConvertString">xmlXPathConvertString</a>     (<a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val);
  92 void        <a href="libxml-xpath.html#xmlXPathInit">xmlXPathInit</a>                    (void);
  93 <a href="libxml-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> <a href="libxml-xpath.html#xmlXPathNewContext">xmlXPathNewContext</a>       (<a href="libxml-tree.html#xmlDocPtr">xmlDocPtr</a> doc);
  94 void        <a href="libxml-xpath.html#xmlXPathFreeContext">xmlXPathFreeContext</a>             (<a href="libxml-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctxt);
  95 <GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="long">long</GTKDOCLINK>        <a href="libxml-xpath.html#xmlXPathOrderDocElems">xmlXPathOrderDocElems</a>           (<a href="libxml-tree.html#xmlDocPtr">xmlDocPtr</a> doc);
  96 <a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> <a href="libxml-xpath.html#xmlXPathEval">xmlXPathEval</a>              (const <a href="libxml-tree.html#xmlChar">xmlChar</a> *str,
  97                                              <a href="libxml-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctx);
  98 <a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> <a href="libxml-xpath.html#xmlXPathEvalExpression">xmlXPathEvalExpression</a>    (const <a href="libxml-tree.html#xmlChar">xmlChar</a> *str,
  99                                              <a href="libxml-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctxt);
 100 int         <a href="libxml-xpath.html#xmlXPathEvalPredicate">xmlXPathEvalPredicate</a>           (<a href="libxml-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctxt,
 101                                              <a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> res);
 102 <a href="libxml-xpath.html#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a> <a href="libxml-xpath.html#xmlXPathCompile">xmlXPathCompile</a>         (const <a href="libxml-tree.html#xmlChar">xmlChar</a> *str);
 103 <a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> <a href="libxml-xpath.html#xmlXPathCompiledEval">xmlXPathCompiledEval</a>      (<a href="libxml-xpath.html#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a> comp,
 104                                              <a href="libxml-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctx);
 105 void        <a href="libxml-xpath.html#xmlXPathFreeCompExpr">xmlXPathFreeCompExpr</a>            (<a href="libxml-xpath.html#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a> comp);
 106 </pre></div><div class="refsect1" lang="en"><h2>Description</h2><p>
 107
 108 </p></div><div class="refsect1" lang="en"><h2>Details</h2><div class="refsect2" lang="en"><h3><a name="xmlXPathContext"></a>struct xmlXPathContext</h3><pre class="programlisting">struct xmlXPathContext {
 109     xmlDocPtr doc;                      /* The current document */
 110     xmlNodePtr node;                    /* The current node */
 111
 112     int nb_variables_unused;            /* unused (hash table) */
 113     int max_variables_unused;           /* unused (hash table) */
 114     xmlHashTablePtr varHash;            /* Hash table of defined variables */
 115
 116     int nb_types;                       /* number of defined types */
 117     int max_types;                      /* max number of types */
 118     xmlXPathTypePtr types;              /* Array of defined types */
 119
 120     int nb_funcs_unused;                /* unused (hash table) */
 121     int max_funcs_unused;               /* unused (hash table) */
 122     xmlHashTablePtr funcHash;           /* Hash table of defined funcs */
 123
 124     int nb_axis;                        /* number of defined axis */
 125     int max_axis;                       /* max number of axis */
 126     xmlXPathAxisPtr axis;               /* Array of defined axis */
 127
 128     /* the namespace nodes of the context node */
 129     xmlNsPtr *namespaces;               /* Array of namespaces */
 130     int nsNr;                           /* number of namespace in scope */
 131     void *user;                         /* function to free */
 132
 133     /* extra variables */
 134     int contextSize;                    /* the context size */
 135     int proximityPosition;              /* the proximity position */
 136
 137     /* extra stuff for XPointer */
 138     int xptr;                           /* it this an XPointer context */
 139     xmlNodePtr here;                    /* for here() */
 140     xmlNodePtr origin;                  /* for origin() */
 141
 142     /* the set of namespace declarations in scope for the expression */
 143     xmlHashTablePtr nsHash;             /* The namespaces hash table */
 144     void *varLookupFunc;                /* variable lookup func */
 145     void *varLookupData;                /* variable lookup data */
 146
 147     /* Possibility to link in an extra item */
 148     void *extra;                        /* needed for XSLT */
 149
 150     /* The function name and URI when calling a function */
 151     const xmlChar *function;
 152     const xmlChar *functionURI;
 153
 154     /* function lookup function and data */
 155     void *funcLookupFunc;               /* function lookup func */
 156     void *funcLookupData;               /* function lookup data */
 157
 158     /* temporary namespace lists kept for walking the namespace axis */
 159     xmlNsPtr *tmpNsList;                /* Array of namespaces */
 160     int tmpNsNr;                        /* number of namespace in scope */
 161 };
 162 </pre><p>
 163 Expression evaluation occurs with respect to a context.
 164 he context consists of:
 165    - a node (the context node)
 166    - a node list (the context node list)
 167    - a set of variable bindings
 168    - a function library
 169    - the set of namespace declarations in scope for the expression
 170 Following the switch to hash tables, this need to be trimmed up at
 171 the next binary incompatible release.</p><p>
 172
 173 </p></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathContextPtr"></a>xmlXPathContextPtr</h3><pre class="programlisting">typedef xmlXPathContext *xmlXPathContextPtr;
 174 </pre><p>
 175
 176 </p></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathParserContext"></a>struct xmlXPathParserContext</h3><pre class="programlisting">struct xmlXPathParserContext {
 177     const xmlChar *cur;                 /* the current char being parsed */
 178     const xmlChar *base;                        /* the full expression */
 179
 180     int error;                          /* error code */
 181
 182     xmlXPathContextPtr  context;        /* the evaluation context */
 183     xmlXPathObjectPtr     value;        /* the current value */
 184     int                 valueNr;        /* number of values stacked */
 185     int                valueMax;        /* max number of values stacked */
 186     xmlXPathObjectPtr *valueTab;        /* stack of values */
 187
 188     xmlXPathCompExprPtr comp;           /* the precompiled expression */
 189     int xptr;                           /* it this an XPointer expression */
 190     xmlNodePtr         ancestor;        /* used for walking preceding axis */
 191 };
 192 </pre><p>
 193 An XPath parser context. It contains pure parsing informations,
 194 an xmlXPathContext, and the stack of objects.</p><p>
 195
 196 </p></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathParserContextPtr"></a>xmlXPathParserContextPtr</h3><pre class="programlisting">typedef xmlXPathParserContext *xmlXPathParserContextPtr;
 197 </pre><p>
 198
 199 </p></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathError"></a>enum xmlXPathError</h3><pre class="programlisting">typedef enum {
 200     XPATH_EXPRESSION_OK = 0,
 201     XPATH_NUMBER_ERROR,
 202     XPATH_UNFINISHED_LITERAL_ERROR,
 203     XPATH_START_LITERAL_ERROR,
 204     XPATH_VARIABLE_REF_ERROR,
 205     XPATH_UNDEF_VARIABLE_ERROR,
 206     XPATH_INVALID_PREDICATE_ERROR,
 207     XPATH_EXPR_ERROR,
 208     XPATH_UNCLOSED_ERROR,
 209     XPATH_UNKNOWN_FUNC_ERROR,
 210     XPATH_INVALID_OPERAND,
 211     XPATH_INVALID_TYPE,
 212     XPATH_INVALID_ARITY,
 213     XPATH_INVALID_CTXT_SIZE,
 214     XPATH_INVALID_CTXT_POSITION,
 215     XPATH_MEMORY_ERROR,
 216     XPTR_SYNTAX_ERROR,
 217     XPTR_RESOURCE_ERROR,
 218     XPTR_SUB_RESOURCE_ERROR,
 219     XPATH_UNDEF_PREFIX_ERROR,
 220     XPATH_ENCODING_ERROR,
 221     XPATH_INVALID_CHAR_ERROR
 222 } xmlXPathError;
 223 </pre><p>
 224
 225 </p></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlNodeSet"></a>struct xmlNodeSet</h3><pre class="programlisting">struct xmlNodeSet {
 226     int nodeNr;                 /* number of nodes in the set */
 227     int nodeMax;                /* size of the array as allocated */
 228     xmlNodePtr *nodeTab;        /* array of nodes in no particular order */
 229     /* @@ with_ns to check wether namespace nodes should be looked at @@ */
 230 };
 231 </pre><p>
 232
 233 </p></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlNodeSetPtr"></a>xmlNodeSetPtr</h3><pre class="programlisting">typedef xmlNodeSet *xmlNodeSetPtr;
 234 </pre><p>
 235
 236 </p></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathObjectType"></a>enum xmlXPathObjectType</h3><pre class="programlisting">typedef enum {
 237     XPATH_UNDEFINED = 0,
 238     XPATH_NODESET = 1,
 239     XPATH_BOOLEAN = 2,
 240     XPATH_NUMBER = 3,
 241     XPATH_STRING = 4,
 242     XPATH_POINT = 5,
 243     XPATH_RANGE = 6,
 244     XPATH_LOCATIONSET = 7,
 245     XPATH_USERS = 8,
 246     XPATH_XSLT_TREE = 9  /* An XSLT value tree, non modifiable */
 247 } xmlXPathObjectType;
 248 </pre><p>
 249
 250 </p></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathObject"></a>struct xmlXPathObject</h3><pre class="programlisting">struct xmlXPathObject {
 251     xmlXPathObjectType type;
 252     xmlNodeSetPtr nodesetval;
 253     int boolval;
 254     double floatval;
 255     xmlChar *stringval;
 256     void *user;
 257     int index;
 258     void *user2;
 259     int index2;
 260 };
 261 </pre><p>
 262
 263 </p></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathObjectPtr"></a>xmlXPathObjectPtr</h3><pre class="programlisting">typedef xmlXPathObject *xmlXPathObjectPtr;
 264 </pre><p>
 265
 266 </p></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathConvertFunc"></a>xmlXPathConvertFunc ()</h3><pre class="programlisting">int         (*xmlXPathConvertFunc)          (<a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> obj,
 267                                              int type);</pre><p>
 268 A conversion function is associated to a type and used to cast
 269 the new type to primitive values.</p><p>
 270
 271 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>obj</tt></i> :</span></td><td>  an XPath object
 272 </td></tr><tr><td><span class="term"><i><tt>type</tt></i> :</span></td><td>  the number of the target type
 273 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>-1 in case of error, 0 otherwise
 274 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathType"></a>struct xmlXPathType</h3><pre class="programlisting">struct xmlXPathType {
 275     const xmlChar         *name;                /* the type name */
 276     xmlXPathConvertFunc func;           /* the conversion function */
 277 };
 278 </pre><p>
 279
 280 </p></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathTypePtr"></a>xmlXPathTypePtr</h3><pre class="programlisting">typedef xmlXPathType *xmlXPathTypePtr;
 281 </pre><p>
 282
 283 </p></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathVariable"></a>struct xmlXPathVariable</h3><pre class="programlisting">struct xmlXPathVariable {
 284     const xmlChar       *name;          /* the variable name */
 285     xmlXPathObjectPtr value;            /* the value */
 286 };
 287 </pre><p>
 288
 289 </p></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathVariablePtr"></a>xmlXPathVariablePtr</h3><pre class="programlisting">typedef xmlXPathVariable *xmlXPathVariablePtr;
 290 </pre><p>
 291
 292 </p></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathEvalFunc"></a>xmlXPathEvalFunc ()</h3><pre class="programlisting">void        (*xmlXPathEvalFunc)             (<a href="libxml-xpath.html#xmlXPathParserContextPtr">xmlXPathParserContextPtr</a> ctxt,
 293                                              int nargs);</pre><p>
 294 An XPath evaluation function, the parameters are on the XPath context stack.</p><p>
 295
 296 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>ctxt</tt></i> :</span></td><td> an XPath parser context
 297 </td></tr><tr><td><span class="term"><i><tt>nargs</tt></i> :</span></td><td> the number of arguments passed to the function
 298 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathFunct"></a>struct xmlXPathFunct</h3><pre class="programlisting">struct xmlXPathFunct {
 299     const xmlChar      *name;           /* the function name */
 300     xmlXPathEvalFunc func;              /* the evaluation function */
 301 };
 302 </pre><p>
 303
 304 </p></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathFuncPtr"></a>xmlXPathFuncPtr</h3><pre class="programlisting">typedef xmlXPathFunct *xmlXPathFuncPtr;
 305 </pre><p>
 306
 307 </p></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathAxisFunc"></a>xmlXPathAxisFunc ()</h3><pre class="programlisting"><a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> (*xmlXPathAxisFunc)       (<a href="libxml-xpath.html#xmlXPathParserContextPtr">xmlXPathParserContextPtr</a> ctxt,
 308                                              <a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> cur);</pre><p>
 309 An axis traversal function. To traverse an axis, the engine calls
 310 the first time with cur == NULL and repeat until the function returns
 311 NULL indicating the end of the axis traversal.</p><p>
 312
 313 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>ctxt</tt></i> :</span></td><td>  the XPath interpreter context
 314 </td></tr><tr><td><span class="term"><i><tt>cur</tt></i> :</span></td><td>  the previous node being explored on that axis
 315 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>the next node in that axis or NULL if at the end of the axis.
 316 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathAxis"></a>struct xmlXPathAxis</h3><pre class="programlisting">struct xmlXPathAxis {
 317     const xmlChar      *name;           /* the axis name */
 318     xmlXPathAxisFunc func;              /* the search function */
 319 };
 320 </pre><p>
 321
 322 </p></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathAxisPtr"></a>xmlXPathAxisPtr</h3><pre class="programlisting">typedef xmlXPathAxis *xmlXPathAxisPtr;
 323 </pre><p>
 324
 325 </p></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathCompExpr"></a>struct xmlXPathCompExpr</h3><pre class="programlisting">struct xmlXPathCompExpr;</pre><p>
 326
 327 </p></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathCompExprPtr"></a>xmlXPathCompExprPtr</h3><pre class="programlisting">typedef xmlXPathCompExpr *xmlXPathCompExprPtr;
 328 </pre><p>
 329
 330 </p></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathFunction"></a>xmlXPathFunction ()</h3><pre class="programlisting">void        (*xmlXPathFunction)             (<a href="libxml-xpath.html#xmlXPathParserContextPtr">xmlXPathParserContextPtr</a> ctxt,
 331                                              int nargs);</pre><p>
 332 An XPath function.
 333 The arguments (if any) are popped out from the context stack
 334 and the result is pushed on the stack.</p><p>
 335
 336 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>ctxt</tt></i> :</span></td><td>  the XPath interprestation context
 337 </td></tr><tr><td><span class="term"><i><tt>nargs</tt></i> :</span></td><td>  the number of arguments
 338 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathIsNaN"></a>xmlXPathIsNaN ()</h3><pre class="programlisting">int         xmlXPathIsNaN                   (<GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="double">double</GTKDOCLINK> val);</pre><p>
 339 Provides a portable <GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="isnan">isnan</GTKDOCLINK>() function to detect whether a double
 340 is a NotaNumber. Based on trio code
 341 http://sourceforge.net/projects/ctrio/</p><p>
 342
 343 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>val</tt></i> :</span></td><td>  a double value
 344 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>1 if the value is a NaN, 0 otherwise
 345 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathIsInf"></a>xmlXPathIsInf ()</h3><pre class="programlisting">int         xmlXPathIsInf                   (<GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="double">double</GTKDOCLINK> val);</pre><p>
 346 Provides a portable <GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="isinf">isinf</GTKDOCLINK>() function to detect whether a double
 347 is a +Infinite or -Infinite. Based on trio code
 348 http://sourceforge.net/projects/ctrio/</p><p>
 349
 350 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>val</tt></i> :</span></td><td>  a double value
 351 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>1 vi the value is +Infinite, -1 if -Infinite, 0 otherwise
 352 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathNodeSetGetLength"></a>xmlXPathNodeSetGetLength()</h3><pre class="programlisting">#define xmlXPathNodeSetGetLength(ns) ((ns) ? (ns)-&gt;nodeNr : 0)
 353 </pre><p>
 354 Implement a functionality similar to the DOM NodeList.length.</p><p>
 355
 356 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>ns</tt></i> :</span></td><td>  a node-set
 357 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathNodeSetItem"></a>xmlXPathNodeSetItem()</h3><pre class="programlisting">#define     xmlXPathNodeSetItem(ns, index)</pre><p>
 358 Implements a functionality similar to the DOM NodeList.<GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="item">item</GTKDOCLINK>().</p><p>
 359
 360 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>ns</tt></i> :</span></td><td>  a node-set
 361 </td></tr><tr><td><span class="term"><i><tt>index</tt></i> :</span></td><td>  index of a node in the set
 362 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathNodeSetIsEmpty"></a>xmlXPathNodeSetIsEmpty()</h3><pre class="programlisting">#define     xmlXPathNodeSetIsEmpty(ns)</pre><p>
 363 Checks whether <i><tt>ns</tt></i> is empty or not.</p><p>
 364
 365 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>ns</tt></i> :</span></td><td> a node-set
 366 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathFreeObject"></a>xmlXPathFreeObject ()</h3><pre class="programlisting">void        xmlXPathFreeObject              (<a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> obj);</pre><p>
 367 Free up an xmlXPathObjectPtr object.</p><p>
 368
 369 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>obj</tt></i> :</span></td><td>  the object to free
 370 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathNodeSetCreate"></a>xmlXPathNodeSetCreate ()</h3><pre class="programlisting"><a href="libxml-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> xmlXPathNodeSetCreate         (<a href="libxml-tree.html#xmlNodePtr">xmlNodePtr</a> val);</pre><p>
 371 Create a new xmlNodeSetPtr of type double and of value <i><tt>val</tt></i></p><p>
 372
 373 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>val</tt></i> :</span></td><td>  an initial xmlNodePtr, or NULL
 374 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>the newly created object.
 375 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathFreeNodeSetList"></a>xmlXPathFreeNodeSetList ()</h3><pre class="programlisting">void        xmlXPathFreeNodeSetList         (<a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> obj);</pre><p>
 376 Free up the xmlXPathObjectPtr <i><tt>obj</tt></i> but don't deallocate the objects in
 377 the list contrary to <a href="libxml-xpath.html#xmlXPathFreeObject">xmlXPathFreeObject</a>().</p><p>
 378
 379 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>obj</tt></i> :</span></td><td>  an existing NodeSetList object
 380 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathFreeNodeSet"></a>xmlXPathFreeNodeSet ()</h3><pre class="programlisting">void        xmlXPathFreeNodeSet             (<a href="libxml-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> obj);</pre><p>
 381 Free the NodeSet compound (not the actual nodes !).</p><p>
 382
 383 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>obj</tt></i> :</span></td><td>  the xmlNodeSetPtr to free
 384 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathObjectCopy"></a>xmlXPathObjectCopy ()</h3><pre class="programlisting"><a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> xmlXPathObjectCopy        (<a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val);</pre><p>
 385 allocate a new copy of a given object</p><p>
 386
 387 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>val</tt></i> :</span></td><td>  the original object
 388 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>the newly created object.
 389 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathCmpNodes"></a>xmlXPathCmpNodes ()</h3><pre class="programlisting">int         xmlXPathCmpNodes                (<a href="libxml-tree.html#xmlNodePtr">xmlNodePtr</a> node1,
 390                                              <a href="libxml-tree.html#xmlNodePtr">xmlNodePtr</a> node2);</pre><p>
 391 Compare two nodes w.r.t document order</p><p>
 392
 393 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>node1</tt></i> :</span></td><td>  the first node
 394 </td></tr><tr><td><span class="term"><i><tt>node2</tt></i> :</span></td><td>  the second node
 395 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>-2 in case of error 1 if first point &lt; second point, 0 if
 396         that's the same node, -1 otherwise
 397 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathCastNumberToBoolean"></a>xmlXPathCastNumberToBoolean ()</h3><pre class="programlisting">int         xmlXPathCastNumberToBoolean     (<GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="double">double</GTKDOCLINK> val);</pre><p>
 398 Converts a number to its boolean value</p><p>
 399
 400 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>val</tt></i> :</span></td><td>  a number
 401 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>the boolean value
 402 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathCastStringToBoolean"></a>xmlXPathCastStringToBoolean ()</h3><pre class="programlisting">int         xmlXPathCastStringToBoolean     (const <a href="libxml-tree.html#xmlChar">xmlChar</a> *val);</pre><p>
 403 Converts a string to its boolean value</p><p>
 404
 405 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>val</tt></i> :</span></td><td>  a string
 406 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>the boolean value
 407 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathCastNodeSetToBoolean"></a>xmlXPathCastNodeSetToBoolean ()</h3><pre class="programlisting">int         xmlXPathCastNodeSetToBoolean    (<a href="libxml-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> ns);</pre><p>
 408 Converts a node-set to its boolean value</p><p>
 409
 410 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>ns</tt></i> :</span></td><td>  a node-set
 411 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>the boolean value
 412 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathCastToBoolean"></a>xmlXPathCastToBoolean ()</h3><pre class="programlisting">int         xmlXPathCastToBoolean           (<a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val);</pre><p>
 413 Converts an XPath object to its boolean value</p><p>
 414
 415 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>val</tt></i> :</span></td><td>  an XPath object
 416 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>the boolean value
 417 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathCastBooleanToNumber"></a>xmlXPathCastBooleanToNumber ()</h3><pre class="programlisting"><GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="double">double</GTKDOCLINK>      xmlXPathCastBooleanToNumber     (int val);</pre><p>
 418 Converts a boolean to its number value</p><p>
 419
 420 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>val</tt></i> :</span></td><td>  a boolean
 421 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>the number value
 422 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathCastStringToNumber"></a>xmlXPathCastStringToNumber ()</h3><pre class="programlisting"><GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="double">double</GTKDOCLINK>      xmlXPathCastStringToNumber      (const <a href="libxml-tree.html#xmlChar">xmlChar</a> *val);</pre><p>
 423 Converts a string to its number value</p><p>
 424
 425 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>val</tt></i> :</span></td><td>  a string
 426 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>the number value
 427 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathCastNodeToNumber"></a>xmlXPathCastNodeToNumber ()</h3><pre class="programlisting"><GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="double">double</GTKDOCLINK>      xmlXPathCastNodeToNumber        (<a href="libxml-tree.html#xmlNodePtr">xmlNodePtr</a> node);</pre><p>
 428 Converts a node to its number value</p><p>
 429
 430 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>node</tt></i> :</span></td><td>  a node
 431 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>the number value
 432 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathCastNodeSetToNumber"></a>xmlXPathCastNodeSetToNumber ()</h3><pre class="programlisting"><GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="double">double</GTKDOCLINK>      xmlXPathCastNodeSetToNumber     (<a href="libxml-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> ns);</pre><p>
 433 Converts a node-set to its number value</p><p>
 434
 435 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>ns</tt></i> :</span></td><td>  a node-set
 436 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>the number value
 437 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathCastToNumber"></a>xmlXPathCastToNumber ()</h3><pre class="programlisting"><GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="double">double</GTKDOCLINK>      xmlXPathCastToNumber            (<a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val);</pre><p>
 438 Converts an XPath object to its number value</p><p>
 439
 440 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>val</tt></i> :</span></td><td>  an XPath object
 441 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>the number value
 442 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathCastBooleanToString"></a>xmlXPathCastBooleanToString ()</h3><pre class="programlisting"><a href="libxml-tree.html#xmlChar">xmlChar</a>*    xmlXPathCastBooleanToString     (int val);</pre><p>
 443 Converts a boolean to its string value.</p><p>
 444
 445 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>val</tt></i> :</span></td><td>  a boolean
 446 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>a newly allocated string.
 447 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathCastNumberToString"></a>xmlXPathCastNumberToString ()</h3><pre class="programlisting"><a href="libxml-tree.html#xmlChar">xmlChar</a>*    xmlXPathCastNumberToString      (<GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="double">double</GTKDOCLINK> val);</pre><p>
 448 Converts a number to its string value.</p><p>
 449
 450 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>val</tt></i> :</span></td><td>  a number
 451 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>a newly allocated string.
 452 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathCastNodeToString"></a>xmlXPathCastNodeToString ()</h3><pre class="programlisting"><a href="libxml-tree.html#xmlChar">xmlChar</a>*    xmlXPathCastNodeToString        (<a href="libxml-tree.html#xmlNodePtr">xmlNodePtr</a> node);</pre><p>
 453 Converts a node to its string value.</p><p>
 454
 455 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>node</tt></i> :</span></td><td>  a node
 456 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>a newly allocated string.
 457 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathCastNodeSetToString"></a>xmlXPathCastNodeSetToString ()</h3><pre class="programlisting"><a href="libxml-tree.html#xmlChar">xmlChar</a>*    xmlXPathCastNodeSetToString     (<a href="libxml-xpath.html#xmlNodeSetPtr">xmlNodeSetPtr</a> ns);</pre><p>
 458 Converts a node-set to its string value.</p><p>
 459
 460 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>ns</tt></i> :</span></td><td>  a node-set
 461 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>a newly allocated string.
 462 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathCastToString"></a>xmlXPathCastToString ()</h3><pre class="programlisting"><a href="libxml-tree.html#xmlChar">xmlChar</a>*    xmlXPathCastToString            (<a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val);</pre><p>
 463 Converts an existing object to its <GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="string">string</GTKDOCLINK>() equivalent</p><p>
 464
 465 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>val</tt></i> :</span></td><td>  an XPath object
 466 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>the string value of the object, NULL in case of error.
 467         A new string is allocated only if needed (<i><tt>val</tt></i> isn't a
 468         string object).
 469 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathConvertBoolean"></a>xmlXPathConvertBoolean ()</h3><pre class="programlisting"><a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> xmlXPathConvertBoolean    (<a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val);</pre><p>
 470 Converts an existing object to its <GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="boolean">boolean</GTKDOCLINK>() equivalent</p><p>
 471
 472 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>val</tt></i> :</span></td><td>  an XPath object
 473 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>the new object, the old one is freed (or the operation
 474         is done directly on <i><tt>val</tt></i>)
 475 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathConvertNumber"></a>xmlXPathConvertNumber ()</h3><pre class="programlisting"><a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> xmlXPathConvertNumber     (<a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val);</pre><p>
 476 Converts an existing object to its <GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="number">number</GTKDOCLINK>() equivalent</p><p>
 477
 478 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>val</tt></i> :</span></td><td>  an XPath object
 479 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>the new object, the old one is freed (or the operation
 480         is done directly on <i><tt>val</tt></i>)
 481 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathConvertString"></a>xmlXPathConvertString ()</h3><pre class="programlisting"><a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> xmlXPathConvertString     (<a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> val);</pre><p>
 482 Converts an existing object to its <GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="string">string</GTKDOCLINK>() equivalent</p><p>
 483
 484 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>val</tt></i> :</span></td><td>  an XPath object
 485 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>the new object, the old one is freed (or the operation
 486         is done directly on <i><tt>val</tt></i>)
 487 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathInit"></a>xmlXPathInit ()</h3><pre class="programlisting">void        xmlXPathInit                    (void);</pre><p>
 488 Initialize the XPath environment</p><p>
 489
 490 </p></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathNewContext"></a>xmlXPathNewContext ()</h3><pre class="programlisting"><a href="libxml-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> xmlXPathNewContext       (<a href="libxml-tree.html#xmlDocPtr">xmlDocPtr</a> doc);</pre><p>
 491 Create a new xmlXPathContext</p><p>
 492
 493 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>doc</tt></i> :</span></td><td>  the XML document
 494 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>the xmlXPathContext just allocated. The caller will need to free it.
 495 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathFreeContext"></a>xmlXPathFreeContext ()</h3><pre class="programlisting">void        xmlXPathFreeContext             (<a href="libxml-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctxt);</pre><p>
 496 Free up an xmlXPathContext</p><p>
 497
 498 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>ctxt</tt></i> :</span></td><td>  the context to free
 499 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathOrderDocElems"></a>xmlXPathOrderDocElems ()</h3><pre class="programlisting"><GTKDOCLINK xmlns="http://www.w3.org/TR/xhtml1/transitional" HREF="long">long</GTKDOCLINK>        xmlXPathOrderDocElems           (<a href="libxml-tree.html#xmlDocPtr">xmlDocPtr</a> doc);</pre><p>
 500 Call this routine to speed up XPath computation on static documents.
 501 This stamps all the element nodes with the document order
 502 Like for line information, the order is kept in the element-&gt;content
 503 field, the value stored is actually - the node number (startting at -1)
 504 to be able to differenciate from line numbers.</p><p>
 505
 506 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>doc</tt></i> :</span></td><td>  an input document
 507 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>the number of element found in the document or -1 in case
 508    of error.
 509 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathEval"></a>xmlXPathEval ()</h3><pre class="programlisting"><a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> xmlXPathEval              (const <a href="libxml-tree.html#xmlChar">xmlChar</a> *str,
 510                                              <a href="libxml-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctx);</pre><p>
 511 Evaluate the XPath Location Path in the given context.</p><p>
 512
 513 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>str</tt></i> :</span></td><td>  the XPath expression
 514 </td></tr><tr><td><span class="term"><i><tt>ctx</tt></i> :</span></td><td>  the XPath context
 515 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>the xmlXPathObjectPtr resulting from the evaluation or NULL.
 516         the caller has to free the object.
 517 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathEvalExpression"></a>xmlXPathEvalExpression ()</h3><pre class="programlisting"><a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> xmlXPathEvalExpression    (const <a href="libxml-tree.html#xmlChar">xmlChar</a> *str,
 518                                              <a href="libxml-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctxt);</pre><p>
 519 Evaluate the XPath expression in the given context.</p><p>
 520
 521 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>str</tt></i> :</span></td><td>  the XPath expression
 522 </td></tr><tr><td><span class="term"><i><tt>ctxt</tt></i> :</span></td><td>  the XPath context
 523 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>the xmlXPathObjectPtr resulting from the evaluation or NULL.
 524         the caller has to free the object.
 525 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathEvalPredicate"></a>xmlXPathEvalPredicate ()</h3><pre class="programlisting">int         xmlXPathEvalPredicate           (<a href="libxml-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctxt,
 526                                              <a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> res);</pre><p>
 527 Evaluate a predicate result for the current node.
 528 A PredicateExpr is evaluated by evaluating the Expr and converting
 529 the result to a boolean. If the result is a number, the result will
 530 be converted to true if the number is equal to the position of the
 531 context node in the context node list (as returned by the position
 532 function) and will be converted to false otherwise; if the result
 533 is not a number, then the result will be converted as if by a call
 534 to the boolean function.</p><p>
 535
 536 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>ctxt</tt></i> :</span></td><td>  the XPath context
 537 </td></tr><tr><td><span class="term"><i><tt>res</tt></i> :</span></td><td>  the Predicate Expression evaluation result
 538 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>1 if predicate is true, 0 otherwise
 539 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathCompile"></a>xmlXPathCompile ()</h3><pre class="programlisting"><a href="libxml-xpath.html#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a> xmlXPathCompile         (const <a href="libxml-tree.html#xmlChar">xmlChar</a> *str);</pre><p>
 540 Compile an XPath expression</p><p>
 541
 542 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>str</tt></i> :</span></td><td>  the XPath expression
 543 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>the xmlXPathCompExprPtr resulting from the compilation or NULL.
 544         the caller has to free the object.
 545 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathCompiledEval"></a>xmlXPathCompiledEval ()</h3><pre class="programlisting"><a href="libxml-xpath.html#xmlXPathObjectPtr">xmlXPathObjectPtr</a> xmlXPathCompiledEval      (<a href="libxml-xpath.html#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a> comp,
 546                                              <a href="libxml-xpath.html#xmlXPathContextPtr">xmlXPathContextPtr</a> ctx);</pre><p>
 547 Evaluate the Precompiled XPath expression in the given context.</p><p>
 548
 549 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>comp</tt></i> :</span></td><td>  the compiled XPath expression
 550 </td></tr><tr><td><span class="term"><i><tt>ctx</tt></i> :</span></td><td>  the XPath context
 551 </td></tr><tr><td><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td><td>the xmlXPathObjectPtr resulting from the evaluation or NULL.
 552         the caller has to free the object.
 553 </td></tr></tbody></table></div></div><hr xmlns="http://www.w3.org/TR/xhtml1/transitional"></hr><div class="refsect2" lang="en"><h3><a name="xmlXPathFreeCompExpr"></a>xmlXPathFreeCompExpr ()</h3><pre class="programlisting">void        xmlXPathFreeCompExpr            (<a href="libxml-xpath.html#xmlXPathCompExprPtr">xmlXPathCompExprPtr</a> comp);</pre><p>
 554 Free up the memory allocated by <i><tt>comp</tt></i></p><p>
 555
 556 </p><div class="variablelist"><table border="0"><col align="left" valign="top"><tbody><tr><td><span class="term"><i><tt>comp</tt></i> :</span></td><td>  an XPATH comp
 557 </td></tr></tbody></table></div></div></div></div><table xmlns="http://www.w3.org/TR/xhtml1/transitional" class="navigation" width="100%" summary="Navigation footer" cellpadding="2" cellspacing="0"><tr valign="middle"><td align="left"><a accesskey="p" href="libxml-HTMLtree.html"><b>&lt;&lt; HTMLtree</b></a></td><td align="right"><a accesskey="n" href="libxml-xpathInternals.html"><b>xpathInternals &gt;&gt;</b></a></td></tr></table></body></html>