NAME

       XML::LibXML::Error - Structured Errors

SYNOPSIS

         eval { ... };
                 if (ref($@)) {
                   # handle a structured error (XML::LibXML::Error object)
                 } elsif ($@) {
                   # error, but not an XML::LibXML::Error object
                 } else {
                   # no error
                 }

         $XML::LibXML::Error::WARNINGS=1;
         $message = $@->as_string();
         print $@->dump();
         $error_domain = $@->domain();
         $error_code = $@->code();
         $error_message = $@->message();
         $error_level = $@->level();
         $filename = $@->file();
         $line = $@->line();
         $nodename = $@->nodename();
         $error_str1 = $@->str1();
         $error_str2 = $@->str2();
         $error_str3 = $@->str3();
         $error_num1 = $@->num1();
         $error_num2 = $@->num2();
         $string = $@->context();
         $offset = $@->column();
         $previous_error = $@->_prev();

DESCRIPTION

       The XML::LibXML::Error class is a tiny frontend to libxml2's structured error support. If
       XML::LibXML is compiled with structured error support, all errors reported by libxml2 are
       transformed to XML::LibXML::Error objects. These objects automatically serialize to the
       corresponding error messages when printed or used in a string operation, but as objects,
       can also be used to get a detailed and structured information about the error that
       occurred.

       Unlike most other XML::LibXML objects, XML::LibXML::Error doesn't wrap an underlying
       libxml2 structure directly, but rather transforms it to a blessed Perl hash reference
       containing the individual fields of the structured error information as hash key-value
       pairs. Individual items (fields) of a structured error can either be obtained directly as
       $@->{field}, or using autoloaded methods such as $@->field() (where field is the field
       name). XML::LibXML::Error objects have the following fields: domain, code, level, file,
       line, nodename, message, str1, str2, str3, num1, num2, and _prev (some of them may be
       undefined).

       $XML::LibXML::Error::WARNINGS
             $XML::LibXML::Error::WARNINGS=1;

           Traditionally, XML::LibXML was suppressing parser warnings by setting libxml2's global
           variable xmlGetWarningsDefaultValue to 0. Since 1.70 we do not change libxml2's global
           variables anymore; for backward compatibility, XML::LibXML suppresses warnings. This
           variable can be set to 1 to enable reporting of these warnings via Perl "warn" and to
           2 to report hem via "die".

       as_string
             $message = $@->as_string();

           This function serializes an XML::LibXML::Error object to a string containing the full
           error message close to the message produced by libxml2 default error handlers and
           tools like xmllint. This method is also used to overload "" operator on
           XML::LibXML::Error, so it is automatically called whenever XML::LibXML::Error object
           is treated as a string (e.g. in print $@).

       dump
             print $@->dump();

           This function serializes an XML::LibXML::Error to a string displaying all fields of
           the error structure individually on separate lines of the form 'name' => 'value'.

       domain
             $error_domain = $@->domain();

           Returns string containing information about what part of the library raised the error.
           Can be one of: "parser", "tree", "namespace", "validity", "HTML parser", "memory",
           "output", "I/O", "ftp", "http", "XInclude", "XPath", "xpointer", "regexp", "Schemas
           datatype", "Schemas parser", "Schemas validity", "Relax-NG parser", "Relax-NG
           validity", "Catalog", "C14N", "XSLT", "validity".

       code
             $error_code = $@->code();

           Returns the actual libxml2 error code. The XML::LibXML::ErrNo module defines constants
           for individual error codes. Currently libxml2 uses over 480 different error codes.

       message
             $error_message = $@->message();

           Returns a human-readable informative error message.

       level
             $error_level = $@->level();

           Returns an integer value describing how consequent is the error.  XML::LibXML::Error
           defines the following constants:

           •   XML_ERR_NONE = 0

           •   XML_ERR_WARNING = 1 : A simple warning.

           •   XML_ERR_ERROR = 2 : A recoverable error.

           •   XML_ERR_FATAL = 3 : A fatal error.

       file
             $filename = $@->file();

           Returns the filename of the file being processed while the error occurred.

       line
             $line = $@->line();

           The line number, if available.

       nodename
             $nodename = $@->nodename();

           Name of the node where error occurred, if available. When this field is non-empty,
           libxml2 actually returned a physical pointer to the specified node.  Due to memory
           management issues, it is very difficult to implement a way to expose the pointer to
           the Perl level as a XML::LibXML::Node. For this reason, XML::LibXML::Error currently
           only exposes the name the node.

       str1
             $error_str1 = $@->str1();

           Error specific. Extra string information.

       str2
             $error_str2 = $@->str2();

           Error specific. Extra string information.

       str3
             $error_str3 = $@->str3();

           Error specific. Extra string information.

       num1
             $error_num1 = $@->num1();

           Error specific. Extra numeric information.

       num2
             $error_num2 = $@->num2();

           In recent libxml2 versions, this value contains a column number of the error or 0 if
           N/A.

       context
             $string = $@->context();

           For parsing errors, this field contains about 80 characters of the XML near the place
           where the error occurred. The field "$@->column()" contains the corresponding offset.
           Where N/A, the field is undefined.

       column
             $offset = $@->column();

           See "$@->column()" above.

       _prev
             $previous_error = $@->_prev();

           This field can possibly hold a reference to another XML::LibXML::Error object
           representing an error which occurred just before this error.

AUTHORS

       Matt Sergeant, Christian Glahn, Petr Pajas

VERSION

       2.0108

COPYRIGHT

       2001-2007, AxKit.com Ltd.

       2002-2006, Christian Glahn.

       2006-2009, Petr Pajas.