.TH xmerl_xpath 3erl "xmerl 1.3.12" "" "Erlang Module Definition"
.SH NAME
xmerl_xpath \- The xmerl_xpath module handles the entire XPath 1.0 spec.
.SH DESCRIPTION
.LP
The xmerl_xpath module handles the entire XPath 1\&.0 spec\&. XPath expressions typically occur in XML attributes and are used to address parts of an XML document\&. The grammar is defined in \fIxmerl_xpath_parse\&.yrl\fR\&\&. The core functions are defined in \fIxmerl_xpath_pred\&.erl\fR\&\&.
.LP
Some useful shell commands for debugging the XPath parser
.LP
.nf

 c(xmerl_xpath_scan).
 yecc:yecc("xmerl_xpath_parse.yrl", "xmerl_xpath_parse", true, []).
 c(xmerl_xpath_parse).

 xmerl_xpath_parse:parse(xmerl_xpath_scan:tokens("position() > -1")).
 xmerl_xpath_parse:parse(xmerl_xpath_scan:tokens("5 * 6 div 2")).
 xmerl_xpath_parse:parse(xmerl_xpath_scan:tokens("5 + 6 mod 2")).
 xmerl_xpath_parse:parse(xmerl_xpath_scan:tokens("5 * 6")).
 xmerl_xpath_parse:parse(xmerl_xpath_scan:tokens("-----6")).
 xmerl_xpath_parse:parse(xmerl_xpath_scan:tokens("parent::node()")).
 xmerl_xpath_parse:parse(xmerl_xpath_scan:tokens("descendant-or-self::node()")).
 xmerl_xpath_parse:parse(xmerl_xpath_scan:tokens("parent::processing-instruction('foo')")).
  
.fi
.SH "DATA TYPES"

.RS 2
.TP 2
.B
docEntity() = #xmlDocument{} | [\fBdocNodes()\fR\&]:

.TP 2
.B
docNodes() = #xmlElement{} | #xmlAttribute{} | #xmlText{} | #xmlPI{} | #xmlComment{} | #xmlNsNode{}:

.TP 2
.B
nodeEntity() = #xmlElement{} | #xmlAttribute{} | #xmlText{} | #xmlPI{} | #xmlComment{} | #xmlNsNode{} | #xmlDocument{}:

.TP 2
.B
option_list():

.RS 2
.LP
Options allows to customize the behaviour of the XPath scanner\&.
.RE

.RS 2
.LP
Possible options are:
.RE

.RS 2
.TP 2
.B
\fI{namespace, #xmlNamespace}\fR\&:
Set namespace nodes, from XmlNamspace, in xmlContext
.TP 2
.B
\fI{namespace, Nodes}\fR\&:
Set namespace nodes in xmlContext\&.
.RE
.TP 2
.B
parentList() = [{atom(), integer()}]:

.TP 2
.B
xPathString() = string():

.RE
.SH EXPORTS
.LP
.B
string(Str, Doc) -> [\fBdocEntity()\fR\&] | Scalar
.br
.RS
.LP
Equivalent to \fBstring(Str, Doc, [])\fR\&\&.
.RE

.LP
.B
string(Str, Doc, Options) -> [\fBdocEntity()\fR\&] | Scalar
.br
.RS
.LP
Equivalent to \fBstring(Str, Doc, [], Doc, Options)\fR\&\&.
.RE

.LP
.B
string(Str, Node, Parents, Doc, Options) -> [\fBdocEntity()\fR\&] | Scalar
.br
.RS
.LP
Types:

.RS 3
Str = \fBxPathString()\fR\&
.br
Node = \fBnodeEntity()\fR\&
.br
Parents = \fBparentList()\fR\&
.br
Doc = \fBnodeEntity()\fR\&
.br
Options = \fBoption_list()\fR\&
.br
Scalar = #xmlObj{}
.br
.RE
.RE
.RS
.LP
Extracts the nodes from the parsed XML tree according to XPath\&. xmlObj is a record with fields type and value, where type is boolean | number | string
.RE

.SH AUTHORS
.LP

.I
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