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XML::LibXML::Error(3)                User Contributed Perl Documentation               XML::LibXML::Error(3)



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 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
       2.0008

COPYRIGHT
       2001-2007, AxKit.com Ltd.

       2002-2006, Christian Glahn.

       2006-2009, Petr Pajas.



perl v5.16.2                                     2012-10-22                            XML::LibXML::Error(3)