XML::XQL (3)
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NAME
XML::XQL - A perl module for querying XML tree structures with XQLSYNOPSIS
use XML::XQL; use XML::XQL::DOM; $parser = new XML::DOM::Parser; $doc = $parser->parsefile ("file.xml"); # Return all elements with tagName='title' under the root element 'book' $query = new XML::XQL::Query (Expr => "book/title"); @result = $query->solve ($doc); $query->dispose; # Avoid memory leaks - Remove circular references # Or (to save some typing) @result = XML::XQL::solve ("book/title", $doc); # Or (to save even more typing) @result = $doc->xql ("book/title");
DESCRIPTION
TheThe current implementation only works with the
To use the
use XML::XQL;
or
use XML::XQL::Strict;
The Strict module only provides the core
See the section ``Additional Features in
This module is still in development. See the To-do list in
If you find a bug, you would do me great favor by sending it to me in the form of a test case. See the file t/xql_template.t that comes with this distribution.
If you have written a cool comparison operator, function, method or
XML::XQL global functions
- solve (QUERY_STRING,INPUT_LIST...)
-
@result = XML::XQL::solve ("doc//book", $doc);
This is provided as a shortcut for:
$query = new XML::XQL::Query (Expr => "doc//book"); @result = $query->solve ($doc); $query->dispose;
Note that with
XML::XQL::DOM, you can also write (see XML::DOM::Node for details):@result = $doc->xql ("doc//book");
- setDocParser (PARSER)
-
Sets the XML::DOM::Parser that is used by the new XQL+document() method. By default it uses an XML::DOM::Parser that was created without any arguments, i.e.
$PARSER = new XML::DOM::Parser;
- defineFunction (NAME,FUNCREF,ARGCOUNT[,ALLOWED_OUTSIDE[,CONST, [QUERY_ARG]]])
-
Defines the XQLfunction (at the global level, i.e. for all newly created queries) with the specifiedNAME. TheARGCOUNTparameter can either be a single number or a reference to a list with numbers. A single number expands to [ARGCOUNT,ARGCOUNT]. The list contains pairs of numbers, indicating the number of arguments that the function allows. The value -1 means infinity. E.g. [2, 5, 7, 9, 12, -1] means that the function can have 2, 3, 4, 5, 7, 8, 9, 12 or more arguments. The number of arguments is checked when parsing theXQLquery string.
The second parameter must be a reference to a Perl function or an anonymous sub. E.g. '\&my_func' or 'sub { ... code ... }'
If
ALLOWED_OUTSIDE(default is 0) is set to 1, the function or method may also be used outside subqueries in node queries. (See NodeQuery parameter in Query constructor)If
CONST(default is 0) is set to 1, the function is considered to be ``constant''. See ``Constant Function Invocations'' for details.If
QUERY_ARG(default is 0) is not -1, the argument with that index is considered to be a 'query parameter'. If the query parameter is a subquery, that returns multiple values, the result list of the function invocation will contain one result value for each value of the subquery. E.g. 'length(book/author)' will return a list of Numbers, denoting the string lengths of all the author elements returned by 'book/author'.Note that only methods (not functions) may appear after a Bang ``!'' operator. This is checked when parsing the
XQLquery string.See also: defineMethod
- generateFunction (NAME,FUNCNAME,RETURN_TYPE[,ARGCOUNT[,ALLOWED_OUTSIDE[,CONST[,QUERY_ARG]]]])
-
Generates and defines an XQLfunction wrapper for the Perl function with the nameFUNCNAME. The function name will beNAMEinXQLquery expressions. The return type should be one of the builtinXQLData Types or a class derived from XML::XQL::PrimitiveType (see ``Adding Data Types''.) See defineFunction for the meaning ofARGCOUNT,ALLOWED_OUTSIDE,CONSTandQUERY_ARG.
Function values are always converted to Perl strings with xql_toString before they are passed to the Perl function implementation. The function return value is cast to an object of type
RETURN_TYPE, or to the empty list [] if the result is undef. It uses expandType to expandXQLprimitive type names. IfRETURN_TYPEis ``*'', it returns the function result as is, unless the function result is undef, in which case it returns []. - defineMethod (NAME,FUNCREF,ARGCOUNT[,ALLOWED_OUTSIDE])
-
Defines the XQLmethod (at the global level, i.e. for all newly created queries) with the specifiedNAME. TheARGCOUNTparameter can either be a single number or a reference to a list with numbers. A single number expands to [ARGCOUNT,ARGCOUNT]. The list contains pairs of numbers, indicating the number of arguments that the method allows. The value -1 means infinity. E.g. [2, 5, 7, 9, 12, -1] means that the method can have 2, 3, 4, 5, 7, 8, 9, 12 or more arguments. The number of arguments is checked when parsing theXQLquery string.
The second parameter must be a reference to a Perl function or an anonymous sub. E.g. '\&my_func' or 'sub { ... code ... }'
If
ALLOWED_OUTSIDE(default is 0) is set to 1, the function or method may also be used outside subqueries in node queries. (See NodeQuery parameter in Query constructor)Note that only methods (not functions) may appear after a Bang ``!'' operator. This is checked when parsing the
XQLquery string.See also: defineFunction
- defineComparisonOperators (NAME=>FUNCREF[,NAME=>FUNCREF]*)
-
Defines XQLcomparison operators at the global level. TheFUNCREFparameters must be a references to a Perl function or an anonymous sub. E.g. '\&my_func' or 'sub { ... code ... }'
E.g. define the operators $my_op$ and $my_op2$:
defineComparisonOperators ('my_op' => \&my_op, 'my_op2' => sub { ... insert code here ... });
- defineElementValueConvertor (TAG_NAME,FUNCREF)
-
Defines that the result of the value() call for Elements with the specified
TAG_NAMEuses the specified function. The function will receive two parameters. The second one is theTAG_NAMEof the Element node and the first parameter is the Element node itself.FUNCREFshould be a reference to a Perl function, e.g. \&my_sub, or an anonymous sub.
E.g. to define that all Elements with tag name 'date-of-birth' should return XML::XQL::Date objects:
defineElementValueConvertor ('date-of-birth', sub { my $elem = shift; # Always pass in the node as the second parameter. This is # the reference node for the object, which is used when # sorting values in document order. new XML::XQL::Date ($elem->xql_text, $elem); });
These converters can only be specified at a global level, not on a per query basis. To undefine a converter, simply pass a
FUNCREFof undef. - defineAttrValueConvertor (ELEM_TAG_NAME,ATTR_NAME,FUNCREF)
-
Defines that the result of the value() call for Attributes with the specified
ATTR_NAMEand a parent Element with the specifiedELEM_TAG_NAMEuses the specified function. AnELEM_TAG_NAMEof ``*'' will match regardless of the tag name of the parent Element. The function will receive 3 parameters. The third one is the tag name of the parent Element (even ifELEM_TAG_NAMEwas ``*''), the second is theATTR_NAMEand the first is the Attribute node itself.FUNCREFshould be a reference to a Perl function, e.g. \&my_sub, or an anonymous sub.
These converters can only be specified at a global level, not on a per query basis. To undefine a converter, simply pass a
FUNCREFof undef. - defineTokenQ (Q)
-
Defines the token for the q// string delimiters at a global level.
The default value for XQL+is 'q', for XML::XQL::Strict it is undef. A value of undef will deactivate this feature.
- defineTokenQQ (QQ)
-
Defines the token for the qq// string delimiters at a global level.
The default value for XQL+is 'qq', for XML::XQL::Strict it is undef. A value of undef will deactivate this feature.
- expandType (TYPE)
-
Used internally to expand type names of XQLprimitive types. E.g. it expands ``Number'' to ``XML::XQL::Number'' and is not case-sensitive, so ``number'' and ``NuMbEr'' will both expand correctly.
- defineExpandedTypes (ALIAS,FULL_NAME[, ...])
-
For each pair of arguments it allows the class name FULL_NAMEto be abbreviated withALIAS. The definitions are used by expandType(). (ALIASis always converted to lowercase internally, because expandType is case-insensitive.)
Overriding the
ALIASfor ``date'', also affects the object type returned by the date() function. - setErrorContextDelimiters (START,END,BOLD_ON,BOLD_OFF)
-
Sets the delimiters used when printing error messages during query evaluation.
The default delimiters on Unix are `tput smul` (underline on) and `tput rmal`
(underline off). On other systems (that don't have tput), the delimiters are
``>>'' and ``<<'' resp.
When printing the error message, the subexpression that caused the error will be enclosed by the delimiters, i.e. underlined on Unix.
For certain subexpressions the significant keyword, e.g. ``$and$'' is enclosed in the bold delimiters
BOLD_ON(default: `tput bold` on Unix, "`` elsewhere) andBOLD_OFF(default: (`tput rmul` . `tput smul`) on Unix, ''" elsewhere, see $BoldOff inXML::XQL::XQL.pm for details.) - isEmptyList (VAR)
-
Returns 1 if VARis [], else 0. Can be used in user defined functions.
Additional Features in XQL+
- Parent operator '..'
-
The '..' operator returns the parent of the current node, where '.' would
return the current node. This is not part of any XQLstandard, because you would normally use return operators, which are not implemented here.
- Sequence operators ';' and ';;'
-
The sequence operators ';' (precedes) and ';;' (immediately precedes) are
not in the XQLspec, but are described in 'The Design ofXQL' by Jonathan Robie who is one of the designers ofXQL. It can be found at <www.texcel.no/whitepapers/xql-design.html> See also theXQLTutorial for a description of what they mean.
- q// and qq// String Tokens
-
String tokens a la q// and qq// are allowed. q// evaluates like Perl's single
quotes and qq// like Perl's double quotes. Note that the default XQLstrings do not allow escaping etc., so it's not possible to define a string with both single and double quotes. If 'q' and 'qq' are not to your liking, you may redefine them to something else or undefine them altogether, by assigning undef to them. E.g:
# at a global level - shared by all queries (that don't (re)define 'q') XML::XQL::defineTokenQ ('k'); XML::XQL::defineTokenQQ (undef); # at a query level - only defined for this query $query = new XML::XQL::Query (Expr => "book/title", q => 'k', qq => undef);
From now on k// works like q// did and qq// doesn't work at all anymore.
- Query strings can have embedded Comments
-
For example:
$queryExpr = "book/title # this comment is inside the query string [. = 'Moby Dick']"; # this comment is outside
- Optional dollar delimiters and case-insensitive XQLkeywords
-
The following XQLkeywords are case-insensitive and the dollar sign delimiters may be omitted: $and$, $or$, $not$, $union$, $intersect$, $to$, $any$, $all$, $eq$, $ne$, $lt$, $gt$, $ge$, $le$, $ieq$, $ine$, $ilt$, $igt$, $ige$, $ile$.
E.g. $AND$, $And$, $aNd$, and, And, aNd are all valid replacements for $and$.
Note that
XQL+comparison operators ($match$, $no_match$, $isa$, $can$) still require dollar delimiters and are case-sensitive. - Comparison operator: $match$ or '=~'
-
E.g. ``book/title =~ '/(Moby|Dick)/']'' will return all book titles containing
Moby or Dick. Note that the match expression needs to be quoted and should
contain the // or m// delimiters for Perl.
When casting the values to be matched, both are converted to Text.
- Comparison operator: $no_match$ or '!~'
-
E.g. ``book/title !~ '/(Moby|Dick)/']'' will return all book titles that don't
contain Moby or Dick. Note that the match expression needs to be quoted and
should contain the // or m// delimiters for Perl.
When casting the values to be matched, both are converted to Text.
- Comparison operator: $isa$
-
E.g. '//. $isa$ ``XML::XQL::Date''' returns all elements for which the value()
function returns an XML::XQL::Date object. (Note that the value() function can
be overridden to return a specific object type for certain elements and
attributes.) It uses expandType to expand XQLprimitive type names.
- Comparison operator: $can$
- E.g. '//. $can$ ``swim''' returns all elements for which the value() function returns an object that implements the (Perl) swim() method. (Note that the value() function can be overridden to return a specific object type for certain elements and attributes.)
- Function: once (QUERY)
-
E.g. 'once(id(``foo''))' will evaluate the QUERYexpression only once per query. Certain query results (like the above example) will always return the same value within a query. Using once() will cache theQUERYresult for the rest of the query.
Note that ``constant'' function invocations are always cached. See also ``Constant Function Invocations''
- Function: subst (QUERY,EXPR,EXPR[,MODIFIERS, [MODE]])
-
E.g. 'subst(book/title, ``[M|m]oby'', ``Dick'', ``g'')' will replace Moby or moby
with Dick globally (``g'') in all book title elements. Underneath it uses Perl's
substitute operator s///. Don't worry about which delimiters are used underneath.
The function returns all the book/titles for which a substitution occurred.
The default MODIFIERSstring is "`` (empty.) The function name may be abbreviated to ''s".
For most Node types, it converts the value() to a string (with xql_toString) to match the string and xql_setValue to set the new value in case it matched. For
XQLprimitives (Boolean, Number, Text) and other data types (e.g. Date) it uses xql_toString to match the String and xql_setValue to set the result. Beware that performing a substitution on a primitive that was found in the originalXQLquery expression, changes the value of that constant.If
MODEis 0 (default), it treats Element nodes differently by matching and replacing text blocks occurring in the Element node. A text block is defined as the concatenation of the raw text of subsequent Text, CDATASection and EntityReference nodes. In this mode it skips embedded Element nodes. If a text block matches, it is replaced by a single Text node, regardless of the original node type(s).If
MODEis 1, it treats Element nodes like the other nodes, i.e. it converts the value() to a string etc. Note that the default implementation of value() calls text(), which normalizes whitespace and includes embedded Element descendants (recursively.) This is probably not what you want to use in most cases, but since I'm not a professional psychic... :-) - Function: map (QUERY,CODE)
-
E.g. 'map(book/title, ``s/[M|m]oby/Dick/g; $_'')' will replace Moby or moby
with Dick globally (``g'') in all book title elements. Underneath it uses Perl's
map operator. The function returns all the book/titles for which a
change occurred.
??? add more specifics
- Function: eval (EXPR[,TYPE])
-
Evaluates the Perl expression EXPRand returns an object of the specifiedTYPE. It uses expandType to expandXQLprimitive type names. If the result of the eval was undef, the empty list [] is returned.
E.g. 'eval(``2 + 5'', ``Number'')' returns a Number object with the value 7, and
'eval(``%ENV{USER}'')' returns a Text object with the user name.Consider using once() to cache the return value, when the invocation will return the same result for each invocation within a query.
??? add more specifics
- Function: new (TYPE[,QUERY[,PAR] *])
-
Creates a new object of the specified object TYPE. The constructor may have any number of arguments. The first argument of the constructor (the 2nd argument of the new() function) is considered to be a 'query parameter'. See defineFunction for a definition of query parameter. It uses expandType to expandXQLprimitive type names.
- Function: document (QUERY) or doc (QUERY)
-
The document() function creates a new XML::XML::Document for each result
of QUERY(QUERYmay be a simple string expression, like ``/usr/enno/file.xml''. See t/xql_document.t or below for an example with a more complexQUERY.)
document() may be abbreviated to doc().
document() uses an XML::DOM::Parser underneath, which can be set with XML::XQL::setDocParser(). By default it uses a parser that was created without any arguments, i.e.
$PARSER = new XML::DOM::Parser;
Let's try a more complex example, assuming $doc contains:
<doc> <file name="file1.xml"/> <file name="file2.xml"/> </doc>
Then the following query will return two XML::XML::Documents, one for file1.xml and one for file2.xml:
@result = XML::XQL::solve ("document(doc/file/@name)", $doc);
The resulting documents can be used as input for following queries, e.g.
@result = XML::XQL::solve ("document(doc/file/@name)/root/bla", $doc);
will return all /root/bla elements from the documents returned by document().
- Method: DOM_nodeType ()
-
Returns the DOMnode type. Note that these are mostly the same as nodeType(), except for CDATASection and EntityReference nodes. DOM_nodeType() returns 4 and 5 respectively, whereas nodeType() returns 3, because they are considered text nodes.
- Function wrappers for Perl builtin functions
-
XQLfunction wrappers have been provided for most Perl builtin functions. When using a Perl builtin function like ``substr'' in anXQL+querry, anXQLfunction wrapper will be generated on the fly. The arguments to these functions may be regularXQL+subqueries (that return one or more values) for a query parameter (see generateFunction for a definition.) Most wrappers of Perl builtin functions have argument 0 for a query parameter, except for: chmod (parameter 1 is the query parameter), chown (2) and utime (2). The following functions have no query parameter, which means that all parameters should be a single value: atan2, rand, srand, sprintf, rename, unlink, system.
The function result is casted to the appropriate
XQLprimitive type (Number, Text or Boolean), or to an empty list if the result was undef.
XPath functions and methods
The following functions were found in the XPath specification:- Function: concat (STRING,STRING, STRING*)
- The concat function returns the concatenation of its arguments.
- Function: starts-with (STRING,STRING)
- The starts-with function returns true if the first argument string starts with the second argument string, and otherwise returns false.
- Function: contains (STRING,STRING)
- The contains function returns true if the first argument string contains the second argument string, and otherwise returns false.
- Function: substring-before (STRING,STRING)
-
The substring-before function returns the substring of the first argument
string that precedes the first occurrence of the second argument string
in the first argument string, or the empty string if the first argument
string does not contain the second argument string. For example,
substring-before("1999/04/01","/") returns 1999.
- Function: substring-after (STRING,STRING)
-
The substring-after function returns the substring of the first argument string
that follows the first occurrence of the second argument string in
the first argument string, or the empty string if the first argument string does
not contain the second argument string. For example,
substring-after("1999/04/01","/") returns 04/01,
and
substring-after("1999/04/01","19") returns 99/04/01.
- Function: substring (STRING,NUMBER[,NUMBER] )
-
The substring function returns the substring of the first argument starting at
the position specified in the second argument with length specified in
the third argument. For example,
substring("12345",2,3) returns "234".
If the third argument is not specified, it returns the substring starting at the position specified in the second argument and continuing to the end of the string. For example,
substring("12345",2) returns "2345".
More precisely, each character in the string is considered to have a numeric position: the position of the first character is 1, the position of the second character is 2 and so on.
NOTE:This differs from the substr method , in which the method treats the position of the first character as 0.The XPath spec says this about rounding, but that is not true in this implementation: The returned substring contains those characters for which the position of the character is greater than or equal to the rounded value of the second argument and, if the third argument is specified, less than the sum of the rounded value of the second argument and the rounded value of the third argument; the comparisons and addition used for the above follow the standard
IEEE754 rules; rounding is done as if by a call to the round function. - Method: string-length ( [ QUERY] )
-
The string-length returns the number of characters in the string.
If the argument is omitted, it defaults to the context node
converted to a string, in other words the string-value of the context node.
Note that the generated
XQLwrapper for the Perl built-in substr does not allow the argument to be omitted. - Method: normalize-space ( [ QUERY] )
-
The normalize-space function returns the argument string with whitespace
normalized by stripping leading and trailing whitespace and replacing
sequences of whitespace characters by a single space. Whitespace characters are
the same as those allowed by the S production in XML. If the argument is omitted, it defaults to the context node converted to a string, in other words the string-value of the context node.
- Function: translate (STRING,STRING,STRING)
-
The translate function returns the first argument string with occurrences of
characters in the second argument string replaced by the character at
the corresponding position in the third argument string. For example,
translate("bar","abc","ABC") returns the string BAr.
If there is a character in the second argument string with no character at a corresponding position in the third argument string (because the second argument string is longer than the third argument string), then occurrences of that character in the first argument string are removed. For example,
translate("--aaa--","abc-","ABC") returns "AAA".
If a character occurs more than once in the second argument string, then the first occurrence determines the replacement character. If the third argument string is longer than the second argument string, then excess characters are ignored.
NOTE:The translate function is not a sufficient solution for case conversion in all languages. A future version may provide additional functions for case conversion.This function was implemented using tr///d.
- Function: sum ( QUERY)
-
The sum function returns the sum of the QUERYresults, by converting the string values of each result to a number.
- Function: floor (NUMBER)
- The floor function returns the largest (closest to positive infinity) number that is not greater than the argument and that is an integer.
- Function: ceiling (NUMBER)
- The ceiling function returns the smallest (closest to negative infinity) number that is not less than the argument and that is an integer.
- Function: round (NUMBER)
- The round function returns the number that is closest to the argument and that is an integer. If there are two such numbers, then the one that is closest to positive infinity is returned.
Implementation Details
- XQLBuiltin Data Types
-
The XQLengine uses the following object classes internally. Only Number, Boolean and Text are considered primitiveXQLtypes:
-
- *
-
XML::XQL::Number
For integers and floating point numbers.
- *
-
XML::XQL::Boolean
For booleans, e.g returned by true() and false().
- *
-
XML::XQL::Text
For string values.
- *
-
XML::XQL::Date
For date, time and date/time values. E.g. returned by the date() function.
- *
-
XML::XQL::Node
Superclass of all
XMLnode types. E.g. all subclasses of XML::DOM::Node subclass from this. - *
-
Perl list reference
Lists of values are passed by reference (i.e. using [] delimiters). The empty list [] has a double meaning. It also means 'undef' in certain situations, e.g. when a function invocation or comparison failed.
-
- Type casting in comparisons
-
When two values are compared in an XMLcomparison (e.g. $eq$) the values are first casted to the same data type. Node values are first replaced by their value() (i.e. theXQLvalue() function is used, which returns a Text value by default, but may return any data type if the user so chooses.) The resulting values are then casted to the type of the object with the highest xql_primType() value. They are as follows: Node (0), Text (1), Number (2), Boolean (3), Date (4), other data types (4 by default, but this may be overridden by the user.)
E.g. if one value is a Text value and the other is a Number, the Text value is cast to a Number and the resulting low-level (Perl) comparison is (for $eq$):
$number->xql_toString == $text->xql_toString
If both were Text values, it would have been
$text1->xql_toString eq $text2->xql_toString
Note that the
XQLspec is vague and even conflicting where it concerns type casting. This implementation resulted after talking to Joe Lapp, one of the spec writers. - Adding Data Types
-
If you want to add your own data type, make sure it derives from
XML::XQL::PrimitiveType and implements the necessary methods.
I will add more stuff here to explain it all, but for now, look at the code for the primitive
XQLtypes or the Date class (XML::XQL::Date in Date.pm.) - Document Order
-
The XQLspec states that query results always return their values in document order, which means the order in which they appeared in the originalXMLdocument. Values extracted from Nodes (e.g. with value(), text(), rawText(), nodeName(), etc.) always have a pointer to the reference node (i.e. the Node from which the value was extracted.) These pointers are acknowledged when (intermediate) result lists are sorted. Currently, the only place where a result list is sorted is in a $union$ expression, which is the only place where the result list can be unordered. (If you find that this is not true, let me know.)
Non-node values that have no associated reference node, always end up at the end of the result list in the order that they were added. The
XQLspec states that the reference node for anXMLAttribute is the Element to which it belongs, and that the order of values with the same reference node is undefined. This means that the order of an Element and its attributes would be undefined. But since theXML::DOMmodule keeps track of the order of the attributes, theXQLengine does the same, and therefore, the attributes of an Element are sorted and appear after their parent Element in a sorted result list. - Constant Function Invocations
-
If a function always returns the same value when given ``constant'' arguments,
the function is considered to be ``constant''. A ``constant'' argument can be
either an XQLprimitive (Number, Boolean, Text) or a ``constant'' function invocation. E.g.
date("12-03-1998") true() sin(0.3) length("abc") date(substr("12-03-1998 is the date", 0, 10))
are constant, but not:
length(book[2])
Results of constant function invocations are cached and calculated only once for each query. See also the
CONSTparameter in defineFunction. It is not necessary to wrap constant function invocations in a once() call.Constant
XQLfunctions are: date, true, false and a lot of theXQL+wrappers for Perl builtin functions. Function wrappers for certain builtins are not made constant on purpose to force the invocation to be evaluated every time, e.g. 'mkdir(``/user/enno/my_dir'', ``0644'')' (although constant in appearance) may return different results for multiple invocations. See %PerlFunc in Plus.pm for details. - Function: count ([QUERY])
-
The count() function has no parameters in the XQLspec. In this implementation it will return the number ofQUERYresults when passed aQUERYparameter.
- Method: text ([RECURSE])
-
When expanding an Element node, the text() method adds the expanded text() value
of sub-Elements. When RECURSEis set to 0 (default is 1), it will not include sub-elements. This is useful e.g. when using the $match$ operator in a recursive context (using the // operator), so it won't return parent Elements when one of the children matches.
- Method: rawText ([RECURSE])
- See text().
SEE ALSO
XML::XQL::Query,The Japanese version of this document can be found on-line at <member.nifty.ne.jp/hippo2000/perltips/xml/xql.htm>
The XML::XQL::Tutorial manual page. The Japanese version can be found at <member.nifty.ne.jp/hippo2000/perltips/xml/xql/tutorial.htm>
The
The Design of
The
The
The XML::Parser and XML::Parser::Expat manual pages.
AUTHOR
Enno Derksen is the original author.Please send bugs, comments and suggestions to T.J. Mather <tjmather@tjmather.com>